Could. Try rephrasing with as a division by a factor of two -- i.e., a right-shift operation (>>4 etc.), and see if that makes a difference.

For something like that, I think it'd be faster/smaller to add another, smaller variable for a countdown... Set it to 500 and decrement it... Then once it's at zero you can do what you want, and reset it to 500.

That way, from a math standpoint, you're not doing anything beyond a DEC and JZ (or whatever the AVR mnemonics might be) and only a couple of bytes of storage. And, you'll only have to perform any big math on the larger number when (or if) it becomes important on its own.