As the title says, which function will give me a result similar to what .substr() does, only for integers?

Thanks!

UPDATE:

Here is what isn't working:

if ($(#itemname).val() == Not Listed) {



        var randVal = Math.random() * 10238946;



        var newVal = randVal.toString().substr(0, 4);



        $(#js_itemid).val(randVal);



        $(#js_price).val(199.99);



    }