diff --git a/DESCRIPTION b/DESCRIPTION
index 357c410..10a877e 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -23,6 +23,5 @@ Collate:
     'cantidades-data.R'
     'to_words.R'
     'spanish.R'
-RoxygenNote: 6.1.1
+RoxygenNote: 7.3.2
 Suggests: testthat, tidyr
-
diff --git a/NAMESPACE b/NAMESPACE
index 9d4a05f..14f3eb5 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -3,4 +3,5 @@
 export(geocode_cadastral)
 export(to_number)
 export(to_words)
+export(to_words2)
 importFrom(magrittr,"%>%")
diff --git a/R/spanish.R b/R/spanish.R
index 9572c93..575adff 100644
--- a/R/spanish.R
+++ b/R/spanish.R
@@ -14,6 +14,11 @@
 #' @section to_words():
 #' Translate to spanish spelled quantities from integers
 #'
+#' @section to_words(2):
+#' Convert numbers or strings of digits to spelled quantities in
+#' Spanish. Numeric input can be as large as 1e22, while strings of
+#' digits can be as large as 60 digits.
+#' 
 #' @section geocode_cadastral():
 #' geocode by longitude and latitude from cadastral references.
 #' Get longitude/latitude from valid cadastral ref. or kml files from catastro.
diff --git a/R/to_words2.R b/R/to_words2.R
new file mode 100644
index 0000000..643233a
--- /dev/null
+++ b/R/to_words2.R
@@ -0,0 +1,182 @@
+#' From integers to spanish spelled quantities.
+#'
+#' Takes any number up to 1e22 or string of numbers
+#' up to 60 digits and returns spanish characters.
+#' The general strategy is to follow the "natural way"
+#' of reading numbers in Spanish: divide them in
+#' groups of 3 from right to left, read them in
+#' hundreds, using mapply, (that's the work of the
+#' function (convert_3_digits())) and attach the suffix
+#' as appropriate (thousands, millions, etc.)
+#' with mapply.
+#' Spanish uses long scale, and that is the one
+#' used in this code (1 billion = 1e12). See
+#' (https://en.wikipedia.org/wiki/Long_and_short_scales)
+#'
+#' @usage to_words2(x)
+#' @keywords spanish, integers, money, quantities.
+#' @param x An integer up to 1e22 or a string of numbers up to 60 digits
+#' @return A string for the same integer number in spanish.
+#' @examples
+#' # Converting numbers (can be negative)
+#' to_words2(31254865)
+#' # converting strings of digits (can have a "-" as the first character)
+#' to_words2("-542687982546720143")
+#' @export
+
+
+to_words2 = function(x){
+  if (is.character(x)) {
+    ## test if it's only digits, else error out:
+      split_x = strsplit(x, "")[[1]]
+      if (split_x[1] == "-"){
+          negative = TRUE
+          x = (split_x[-1] |> paste(collapse = ""))
+    }
+    if (!grepl("\\D", x)){
+      y = x
+      if (nchar(y) > 60){
+          stop("That there is a big number. I ran out of words.")
+      }
+    }else{
+      stop("String should contain only numbers.")
+    }
+  } else if (is.numeric(x)) {
+      if (x != round(x, 0)) {
+          stop("Number should be an integer!")
+      }
+      if (x < 0){
+          negative = TRUE
+          x = abs(x)
+      }
+      if (x > 1e22) {
+          warning(paste0(
+              "Number is big, precision errors may be present",
+              " in the output.\nSee https://stackoverflow.com/",
+              "questions/23600569/r-wrong-arithmetic-for-big-numbers"
+          ))
+      }
+      if (x >= 1e23) {
+          stop(paste0(
+              "Errors due to precion are so big that results ",
+              "became useless."
+          ))
+      }
+      y = format(x, scientific = FALSE)
+  }else{
+      stop("Input should be either numeric or a string of numbers.")
+  }
+  
+  groups = regmatches(y, gregexpr(".{1,3}(?=(.{3})*$)", y, perl = TRUE))[[1]]
+
+  long_text = sapply(groups, convert_3_digits)
+  big_units = c("", " mil", " millones", " mil", " billones", " mil",
+                " trillones", " mil", " cuatrillones", " mil",
+                " quintillones", " mil", " sextillones", " mil",
+                " septillones", " mil", " octillones", " mil",
+                " nonillones", " mil")
+  raw_text = mapply(paste0, long_text, rev(big_units[1:length(groups)]))
+  negative_text = ifelse(negative == TRUE,
+                         "menos ",
+                         "")
+  cleaned_text = paste0(
+          negative_text,
+          clean_text2(paste(raw_text, collapse = " "))
+  )
+  return(cleaned_text)
+}
+
+clean_text2 = function(n){
+  ## We are aware that many of this replacements can
+  ## be "summarized" by the use of some regex.
+  ## We choose to keep the replacements readable at
+  ## the (cheap) expense of making the code longer.
+  ## regex can add 1 problem to your 99 on list:
+  ## https://xkcd.com/1171
+  ## fix hundreds
+  n = gsub("cerocientos", "", n)
+  n = gsub("unocientos", "ciento", n)
+  n = gsub("cincocientos", "quinientos", n)
+  n = gsub("sietecientos", "setecientos", n)
+  n = gsub("nuevecientos", "novecientos", n)
+  ## fix tenths
+  n = gsub("cerodiez", "", n)
+  n = gsub("unodiez", "diez", n)
+  n = gsub("dosdiez", "veinte", n)
+  n = gsub("tresdiez", "treinta", n)
+  n = gsub("cuatrodiez", "cuarenta", n)
+  n = gsub("cincodiez", "cincuenta", n)
+  n = gsub("seisdiez", "sesenta", n)
+  n = gsub("sietediez", "setenta", n)
+  n = gsub("ochodiez", "ochenta", n)
+  n = gsub("nuevediez", "noventa", n)
+  ## fix teens
+  n = gsub("diez y uno", "once", n)
+  n = gsub("diez y dos", "doce", n)
+  n = gsub("diez y tres", "trece", n)
+  n = gsub("diez y cuatro", "catorce", n)
+  n = gsub("diez y cinco", "quince", n)
+  ## fix thousands
+  n = gsub("cero mil ", "", n)
+  n = gsub("uno mil", "mil", n)
+  n = gsub("veinte y mil", "veinte y un  mil", n)
+  n = gsub("treinta y mil", "treinta y un  mil", n)
+  n = gsub("cuarenta y mil", "cuarenta y un  mil", n)
+  n = gsub("cincuenta y mil", "cincuenta y un  mil", n)
+  n = gsub("sesenta y mil", "sesenta y un  mil", n)
+  n = gsub("setenta y mil", "setenta y un  mil", n)
+  n = gsub("ochenta y mil", "ochenta y un  mil", n)
+  n = gsub("noventa y mil", "noventa y un  mil", n)
+  ## fix millions
+  n = gsub("cero millones", "millones", n)
+  n = gsub("^millones", "un millón", n)
+  ## fix billions (1e12)
+  n = gsub("billones millones", "billones", n)
+  n = gsub("uno billones", "un billón", n)
+  n = gsub("cero billones", "billones", n)
+  ## fix trillions (1e18)
+  n = gsub("trillones billones", "trillones", n)
+  n = gsub("uno trillones", "un trillón", n)
+  n = gsub("cero trillones", "trillones", n)
+  ## fix cuatrillions (1e24)
+  n = gsub("cuatrillones trillones", "cuatrillones", n)
+  n = gsub("uno cuatrillones", "un cuatrillón", n)
+  n = gsub("cero cuatrillones", "cuatrillones", n)
+  ## fix quintillions (1e30)
+  n = gsub("quintillones cuatrillones", "quintillones", n)
+  n = gsub("uno quintillones", "un quintillón", n)
+  n = gsub("cero quintillones", "quintillones", n)
+  ## fix sextillions (1e36)
+  n = gsub("sextillones quintillones", "sextillones", n)
+  n = gsub("uno sextillones", "un sextillón", n)
+  n = gsub("cero sextillones", "sextillones", n)
+  ## fix septillions (1e42)
+  n = gsub("septillones sextillones", "septillones", n)
+  n = gsub("uno septillones", "un septillón", n)
+  n = gsub("cero septillones", "septillones", n)
+  ## fix octillions (1e48)
+  n = gsub("octillones septillones", "octillones", n)
+  n = gsub("uno octillones", "un octillón", n)
+  n = gsub("cero octillones", "octillones", n)
+  ## fix ninillions (1e54)
+  n = gsub("nonillones octillones", "nonillones", n)
+  n = gsub("uno nonillones", "un nonillón", n)
+  n = gsub("cero nonillones", "nonillones", n)
+  ## general cleaning
+  n = gsub(" {2,}", " ", n)
+  n = gsub("^ +y ", "", n)
+  n = gsub(" y? ?cero$", "", n)
+  n = gsub("^ciento$", "cien", n)
+  n = gsub("^ ", "", n)
+}
+
+convert_3_digits = function(string_value){
+  units = c("cero", "uno", "dos", "tres", "cuatro",
+            "cinco", "seis", "siete", "ocho", "nueve")
+
+  string_value = sprintf("%03d", as.integer(string_value))
+  digits = strsplit(string_value, "")[[1]]
+  a = sapply(digits, function(x) units[as.integer(x) + 1])
+  raw_text = mapply(paste0, a, c("cientos", "diez y", ""))
+  clean_text2(paste(raw_text, collapse = " "))
+}
diff --git a/man/spanish.Rd b/man/spanish.Rd
index a788ddd..5bdaa5e 100644
--- a/man/spanish.Rd
+++ b/man/spanish.Rd
@@ -2,8 +2,8 @@
 % Please edit documentation in R/spanish.R
 \docType{package}
 \name{spanish}
-\alias{spanish}
 \alias{spanish-package}
+\alias{spanish}
 \title{spanish: A package for spanish related data functions.}
 \description{
 The spanish package provides some functions for spanish data:
@@ -24,9 +24,28 @@ The upper limit is up to the millions range. Cents must be removed.
 Translate to spanish spelled quantities from integers
 }
 
+\section{to_words(2)}{
+
+Convert numbers or strings of digits to spelled quantities in
+Spanish. Numeric input can be as large as 1e22, while strings of
+digits can be as large as 60 digits.
+}
+
 \section{geocode_cadastral()}{
 
 geocode by longitude and latitude from cadastral references.
 Get longitude/latitude from valid cadastral ref. or kml files from catastro.
 }
 
+\seealso{
+Useful links:
+\itemize{
+  \item \url{https://github.com/verajosemanuel}
+  \item Report bugs at \url{https://github.com/verajosemanuel/spanish/issues}
+}
+
+}
+\author{
+\strong{Maintainer}: Jose Manuel Vera Oteo \email{vera.josemanuel@gmail.com}
+
+}
diff --git a/man/to_words2.Rd b/man/to_words2.Rd
new file mode 100644
index 0000000..52b226b
--- /dev/null
+++ b/man/to_words2.Rd
@@ -0,0 +1,38 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/to_words2.R
+\name{to_words2}
+\alias{to_words2}
+\title{From integers to spanish spelled quantities.}
+\usage{
+to_words2(x)
+}
+\arguments{
+\item{x}{An integer up to 1e22 or a string of numbers up to 60 digits}
+}
+\value{
+A string for the same integer number in spanish.
+}
+\description{
+Takes any number up to 1e22 or string of numbers
+up to 60 digits and returns spanish characters.
+The general strategy is to follow the "natural way"
+of reading numbers in Spanish: divide them in
+groups of 3 from right to left, read them in
+hundreds, using mapply, (that's the work of the
+function (convert_3_digits())) and attach the suffix
+as appropriate (thousands, millions, etc.)
+with mapply.
+Spanish uses long scale, and that is the one
+used in this code (1 billion = 1e12). See
+(https://en.wikipedia.org/wiki/Long_and_short_scales)
+}
+\examples{
+# Converting numbers (can be negative)
+to_words2(31254865)
+# converting strings of digits (can have a "-" as the first character)
+to_words2("-542687982546720143")
+}
+\keyword{integers,}
+\keyword{money,}
+\keyword{quantities.}
+\keyword{spanish,}