#!/usr/bin/perl
use Math::BigInt;

my $bignum = Math::BigInt->new(9007199254740991);
print $bignum->as_bin(),"\n";

######################################################## 

use bigint;

my $bignum = 9007199254740991;
print $bignum->as_bin(),"\n";

__END__ 

##</code><code>##

0b11111111111111111111111111111111111111111111111111110
0b11111111111111111111111111111111111111111111111111111