That made me wonder how the game determines if the number is a prime or not. Turns out it's the Miller-Rabin test with a deterministic variant used for the rang

That made me wonder how the game determines if the number is a prime or not. Turns out it's the Miller-Rabin test with a deterministic variant used for the range (up to 2^53) the game supports. I don't know why the game internally uses a bigint implementation while only supporting numbers up to 2^53 though...