In regards to being too large for a 32bit app to handle. No, that isn't an actual error message, but it will cause errors in what you're trying to display. "Loss of precision" or "error"... it's still a problem.
//echo -a $bytes(123456789123456789123456789,b)
For basic uses, it works very well. But I've seen people write games where the "money" they give out is in the millions for a given task and that adds up very quickly which is why I mentioned it.