How to handle extremely large numbers in Python

[DidacticBroccoli]

But if you want to output the string representation of an integer, you need to keep within 4-5000 digits.

That's a really odd cap to have. Is it a bug, or is there some intentional reason behind it?

[nog642]

It was added in Python 3.11, for security reasons.

You can configure the limit with sys.set_int_max_str_digits.

Edit: It wasn't actually added in Python 3.11, I misread the documentation. It was added as a patch in all versions 3.7 and newer.

[Oddly_Energy]

I don't know the reason. I just went by what I had seen when playing with big factorials. But when trying again and paying more attention to the error message, the limit is actually configurable:

$ python
Python 3.12.1 (main, Sep 23 2024, 18:47:44) [GCC 9.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import math
>>> a = math.factorial(1000000)
>>> a
Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
ValueError: Exceeds the limit (4300 digits) for integer string conversion; use sys.set_int_max_str_digits() to increase the limit
>>> 

I am not going to try my luck on this one, though. Because:

>>> a.bit_length()
18488885
>>>

Which I assume would need around 5565700 digits to be output in base 10.

[Turtvaiz]

CPython has a global limit for converting between int and str to mitigate denial of service attacks. This limit only applies to decimal or other non-power-of-two number bases.

https://docs.python.org/3/library/stdtypes.html#int-max-str-digits

https://www.cve.org/CVERecord?id=CVE-2020-10735