If it wasn't specified then he means UPC-A
UPC-A codes are made up of 12 decimal digits (there's a few non-decimal fixed ones in there as well but we don't need to worry about them if we're just interested in the number available.) However, the last decimal digit is a checksum, so that doesn't count either. That gives us 11 decimal digits to play with - the first digit isn't a free for all, I think 1-5 are reserved for various special uses while 0 and 6-9 aren't - but I'm ignoring practicalities for this example.
This gives us therefore however many combinations we can make with 11 decimal digits, which I make as 100,000,000,000 - 100 (US) billion or 100 thousand million to be more specific