If returning wrong result

Not sure if I'm not seeing something or what, but I have a simple id validation

$id = '2s2';

var_dump($id);
var_dump($id*1);
if ($id != ($id*1) || $id <= 0) {
    die('wrong id');
}
die('here?');

The result:

string '2s2' (length=3)
int 2
here?

It checks if id is the same as id multiplied by 1 or if the value is zero or lower. Since, the value of $id = '2s2; it is not the same ( as can be seen in the dump ).

Why is this not echoing wrong id ?