Is there a way to get the largest integer one can use in Python? [duplicate]

Python has arbitrary precision integers so there is no true fixed maximum. You're only limited by available memory.

In Python 2, there are two types, int and long. ints use a C type, while longs are arbitrary precision. You can use sys.maxint to find the maximum int. But ints are automatically promoted to long, so you usually don't need to worry about it:

sys.maxint + 1

works fine and returns a long.

sys.maxint does not even exist in Python 3, since int and long were unified into a single arbitrary precision int type.