Factors of a very large whole number

fletch

Does anybody know how to find the factors of a verry large whole number? The "Sieve of Eratosthenes" is too slow....
Thanks
(PS I have to be able to do this on paper, no computers can be used)

Pherekydes

Cryptography challenge?

Factoring the numbers is the easiest part.

Raising something to the power of a (possibly) six digit number is the bitch!:p

fletch

Yeh was a Cyptology challenge....turns out it was Fermats Theorem...(I know where not to come when I need some maths problem solved quickly!)

Pherekydes

I know what you're going through. I went through the same this time last year.

P.S. Of course, I have the two €50 checks to show for it.:D

P.P.S. Well I don't anymore. One went to the charity and I spent the other.;)

jcf

Slow coach wrote:

Cryptography challenge?

Factoring the numbers is the easiest part.

Raising something to the power of a (possibly) six digit number is the bitch!:p

I think you have that the wrong way there, its factoring large numbers thats
a bitch and multiplying/raising to powers thats easier (although a 6 digit index is difficult, factoring the result would be far far more difficult)

Pherekydes

jcf wrote:

I think you have that the wrong way there, its factoring large numbers thats
a bitch and multiplying/raising to powers thats easier (although a 6 digit index is difficult, factoring the result would be far far more difficult)

OK. I found it (dead) easy to factor the 7 digit numbers.

And I found it hard doing the other stuff.

jcf

Sorry i thought you were talking about factoring 100+ digit numbers