use Math::BaseCalc;

$calc36 = new Math::BaseCalc(digits=>[0..9,'A'..'Z'];
$calc10  = new Math::BaseCalc(digits=>[0..9]);

$in_base_36 = $calc36->to_base($calc10->from_base('4345317546') );

$in_base_10 = $calc10->to_base( $calc36->from_base('DA5BG') );