Prime Factoring Large Numbers

Date: 03/28/2003 at 14:18:26
From: Sajid
Subject: Prime factorization

What are the prime factors of 5515596313?

We have been trying to solve this for a long time, but always get 
stuck. It's such a big number that even spending days on it, we 
couldn't do it. We'll all be thankful, if you could please help us.

Date: 03/28/2003 at 18:13:43
From: Doctor Terrel
Subject: Re: Prime factorization

Dear Sajid,

That's a big number! No wonder you've been having troubles.  

You're in luck. Nowadays there are many computer programs available 
online that will tell you whether or not a big number is prime. Other 
programs even give you the prime factorization as well.

I'm lucky to have a simple program on my hard drive that is powerful 
enough for many numbers like yours. So I just entered it and pushed a 
button, and bingo!  there it was - 71593 * 77041.

Let me give you the URLs of two places you can go to find the 
factorizer programs yourself. 

   Factor Applet - Jack Brennen
   http://www.brennen.net/primes/FactorApplet.html 

   Factoris - WWW Interactive Mathematics Server 
   http://wims.unice.fr/wims/en_home.html 
   (choose Factoris to get to the page that does the factoring)

Good luck.

- Doctor Terrel, The Math Forum
  http://mathforum.org/dr.math/