Issue with using MAX Hackers past 100 Billion. It screws up purple bar. Otherwise; good game. Finishes playthroughs in about 18 minutes or less.
I couldn't finish the game because of the overflow error :(
Like aguydude said you can use 64 bits (long and ulong types) if you're using integers, that will get you a long way (har har). Alternatively you can use float, up to 10^38, or double, up to 10^308.
Pretty simple game but still fun for its duration. Keep it up!