Original sentence: The number of theoretically possible UUIDs is therefore 216 × 8 = 2128 = 25616 or about 3.4 × 1038.This means that 1 trillion UUIDs would have to be created every nanosecond for slightly more than 10 billion years to exhaust the number of UUIDs
Edited sentence: The number of theoretically possible UUIDs is therefore about 3 × 1038