Well, I do not really understand what you need. You mentioned you only need integers and powers of ten.
But, you also talked about ‘E’ values and typing .000…001 …
I looked at the PHP POW function and it should be able to create any decimal power you need. The only issue is that it will not go over a max amount which is limited by the way that PHP stores numbers. PHP uses floats, or signed 32-bit ints to store numbers. This is a tight limit on size of the results and usually turns it into an ‘E’ value.
You could use GMP math functions, but, they limit it to 10-to-the-50th powers.
You can use the BC-math version which is supposed to be for larger numbers. But, the question for you is why you need this and does it have to be a number? If your numbers are used in math functions, then might try the BCmath fuctions. Such as bcpow(); If not needed for math, but, for display purposes, you could create a simple text function to simulate the numbers.
Sorry if I have not given you an exact answer, but, 32 bits is 32 bits… Hope it helps someway…