How to use Arrays to keep track of gigantic numbers

[Asif Hirai]

I am planning on creating a prime number generator, my only problem is this: how am I going to keep track of the gigantic prime numbers? I want to use an array

srand(time(NULL));
int *key1 = new int;
int *key2 = new int;
int x = 0;

for (x=0;x<1025;x++){
   key1[x] = ((int)rand())%10;
   key2[x] = ((int)rand())%10;
}

but here's my other problem: how am I going to manipulate the array? Do I treat it as a matrix or something else? I am pretty sure I can't just use it as a single large number, but what am I going to do?

[LB]

Try: unsigned long long int x = 18446744073709551615UL; //64-bit integer
The UL means Unsigned Long long

[Asif Hirai]

I need bigger numbers than that to use in any reasonable cryptography uses. it would take a minimum of 2¹² bit key (4096 bit) or 2 of 500 digit primes to generate a public key long enough to warrant a sufficient sense of security. I know how to generate the numbers, what I need to know is how to multiply, divide, modulus, raise, and do complex math to the numbers.

[LB]

I'd recommend not reinventing the wheel and just going with a bignum library. For example:
http://www.ttmath.org/ - You can use something like ttmath::UInt<TTMATH_BITS(4096)>