Calculations on large binary or integer numbers

I have a database with some large integer values, in the order of 500 bits. I read in the values from a yaml file as strings in decimal notation. I need to do some simple arithmetic and converting to hexadecimal. ‘int’ is limited to 64 bits and ‘decimal’ is limited to 28 decimal digits which is also far to small.

I could of course create a bigint library myself to operate on large integers but are there any builtin solutions or libraries that I could use?

A simple search in Search — Typst: Universe gives peano, which seems like something useful.