my $prod = Math::BigInt->new( 1 );
    my %digits;
    $digits{ $_ } ++ for split m{}, $nVal->bstr();
    $prod->bmul( $_ ) for
       map {
          $digits{ $_ } > 1
          ? Math::BigInt->new( $_ )->bpow( $digits{ $_ } )
          : $_
          } keys %digits;