#!/usr/bin/perl
use strict;
use warnings;

my @factors = Factor_It( 20 );
print "$_\n" for @factors;

sub Factor_It {
    my $number = shift;
    my @factors;
    for ( 2 .. int $number / 2 ) {        
        push @factors, $_ unless $number % $_;
    }
    return (1, @factors, $number);
}