i'm trying to convert the radix number that php returns when you don't have a decimal ($num =02092; returns 16 instead of 02092) and in js: (var num = 02092; returns 2092 instead of 02092).
In JavaScript, you could use parseInt to get the number you want, assuming it's in string format:
var num = '0123';
parseInt( num, 10 ); // 123
Specifying 10 as the radix will force it to be base 10.
If it's already in integer format, and you know it's in base 8, you can convert it with:
var num = 0123;
num = ~~num.toString( 8 );
It seems like there may be a better way to do this, but that's the first thing that comes to my mind.
Also, since it's not intuitive, the ~~ is just a shortcut that I use to force something to be an integer.