number to human readable text

readable_number.js

function readable_number(num){
	var bits_a = ["thousand", "million", "billion", "trillion", "zillion"];
	var bits_b = ["ten", "twenty", "thirty", "fourty", "fifty", "sixty", "seventy", "eighty", "ninety"];
	var bits_c = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", "eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"];

	if (num==0){return 'zero';}

	var result = (num<0)?'minus ':'';

	num = Math.abs(num);
	for(var i=bits_a.lenght; i>0; i--){
		var p = pow(1000, i);
		if (num > p){
			var b = Math.floor(num/p);
			num -= p * b;
			result += readable_number(b) + ' ' + bits_a[i-1];
			result += ((num)?', ':'');
		}
	}
	if (num > 100){
		var b = Math.floor(num/100);
		num -= 100 * b;
		result += readable_number(b) + ' hundred' + ((num)?' and ':' ');
	}
	if (num >= 20){
		var b = Math.floor(num/10);
		num -= 10 * b;
		result += bits_b[b-1] + ' ';
	}
	if (num){
		result += bits_c[num-1];
	}
	return result;
}