if you're looking for speed (and you know $number is always less than 10 digits), why not do it this way:

sub three {
    my $number = "213";
    my $padded = substr("000000000".$number, -9);
    #print $padded,"\n";
}
[download]

cheers,
Aldo

__END__
$_=q,just perl,,s, , another ,,s,$, hacker,,print;
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