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

use v5.10;
use strict;
use warnings;
use Math::BigInt lib => 'FastCalc';

my $n = 123;

my $x = Math::BigInt->new($n);
say $x;
say $x->digit(-1);

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In reply to Re: Using the Math::BigFloat->digit() method by Khen1950fx
in thread Using the Math::BigFloat->digit() method by Athanasius

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