if you use bigint; you will have never have to worry. 
#bad
print 2**59, "\n";    #5.76460752303423e+017
print 2**59+1, "\n";  #5.76460752303423e+017

[download]
#good
use bigint;

print 2**59, "\n";   #576460752303423488
print 2**59+1, "\n"; #576460752303423489

[download]

In reply to Re: Integer overflow question by holli
in thread Integer overflow question by martell

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