Arbitrary-precision arithmetic (sometimes named bignum or bigint) is used to represent really big numbers, it can be used to make endless mode really endless (if player has enough space and memory :D)
Lua has some bigint libraries, although I didn't try them myself, you can google "lua bigint" to search for some open libraries or implement it yourself
Only caveats with bigint with little increased memory usage and little lower speed of operations, but it should be in acceptable range even on low-end systems, but it's a necessary tradeoff to make game better
If you want to implement it, I suggest to leave a second "You Win!" message at 2^1024 score, so that old records will be valid
https://en.wikipedia.org/wiki/Arbitrary-precision_arithmetic
In computer science, arbitrary-precision arithmetic, also called bignum arithmetic, multiple-precision arithmetic, or sometimes infinite-precision arithmetic, indicates that calculations are performed on numbers whose digits of precision are potentially limited only by the available memory of the host system. This contrasts with the faster fixe...