I'm trying to find to prime numbers that when multiplied equal a large number. I have the program written in C. Currently it uses Integers. When I try to use a float, it gives of odd results. It doesn't loop correctly or do anything correctly. I don't think a float is large enough anyway. I need to be able to work with 100+ digit numbers... Any ideas?

(Yes, if you want to guess this is for the RSA Challange._I have no chance but I can dream...)