I remember a class about dividing and finding the reminder of realy big integers. Nobody quite understood it but it had something to do with normalization of the divisor.
The class was based on the 13 chapter of

Per Brinch Hansen.
Studies in Computational Science: Parallel Programming Paradigms.
Prentice Hall, 1995.
ISBN 0-13-439324-4 (Hard cover)

[edited by - wolverine on June 6, 2004 5:25:06 AM]

Yes this has to do with the cyclic groups, or an operator you might now better : % (modulo). This is central in the number theories.

For instance : 216545648118198488489445131568%100 = 68, pretty easy.

More generally a modulo can be computed in linear time considering the size of the number. Which means your computer could well compute the remainder of a number with billion of digits by a smaller number in a few seconds. But the remainder is not the quotient. Getting it requires more computation. And factoring a big number, that is finding all the divisors is infinitely more complex.