How can I convert an integer into its verbal representation?

Question

Is there a library or a class/function that I can use to convert an integer to it\'s verbal representation?

Example input:

4,567,788`

Answer 1

Here is the spanish version:

        public static string numeroALetras(int number)
    {
        if (number == 0)
            return "cero";

        if (number < 0)
            return "menos " + numeroALetras(Math.Abs(number));

        string words = "";

        if ((number / 1000000) > 0)
        {
            words += numeroALetras(number / 1000000) + " millón ";
            number %= 1000000;
        }

        if ((number / 1000) > 0)
        {
            words += (number / 1000) == 1? "mil ": numeroALetras(number / 1000) + " mil ";
            number %= 1000;
        }
        if ((number / 100) == 1)
        {
            if (number == 100)
                words += "cien";
            else words += (number / 100)> 1? numeroALetras(number / 100) + " ciento ":"ciento ";
            number %= 100;
        }
        if ((number / 100) > 1)
        {
            var hundredMap = new[] {"","", "dosc", "tresc", "cuatroc", "quin", "seisc", "sietec", "ochoc", "novec" };
            if (number > 199)
                words += hundredMap[number/100] + "ientos ";
            else {
                words += numeroALetras(number / 100) + " ientos ";
            }
            number %= 100;
        }

        if (number > 0)
        {
            if (words != "")
                words += " ";

            var unitsMap = new[] { "cero", "uno", "dos", "tres", "cuatro", "cinco", "seis", "siete", "ocho", "nueve", "diez", "once", "doce", "trece", "catorce", "quince", "dieciseis", "diecisiete", "dieciocho", "diecinueve", "veinte" };
            var tensMap = new[] { "cero", "diez", "veinti", "treinta", "cuarenta", "cincuenta", "sesenta", "setenta", "ochenta", "noventa" };

            if (number < 21)
                words += unitsMap[number];
            else
            {                    
                words += tensMap[number / 10];
                if ((number % 10) > 0)
                    words += ((number % 10)>2?" y ": "") + unitsMap[number % 10];                    
            }
        }

        return words;
    }