@hackage numerals-base0.3

This package contains machinery to construct functions that convert numbers to number words. It allows you to write a function which converts a number like 142 to the string "one hundred and forty-two".

The documentation for the Text.Numeral module contains an high level overview of the package.

If you just want to convert numbers to number words in a specific language you should probably use the numerals package. That package also contains numerous examples on how to use the functions in this package.