most negative value for python

In Python, ints will auto-promote to long (bigint).

Here you can see the result is promoted to a long

>>> from sys import maxint
>>> type(-maxint)
<type 'int'>
>>> type(-maxint-1)
<type 'int'>
>>> type(-maxint-2)
<type 'long'>
>>> 

note that the usual convention for signed values is to have one more negative number than positive, so in this case -2147483648 is still an int