What two things did the Babylonians have as part of their number system that the Egyptians lacked?

First thing that the Babylonians had and the Egyptians did not is place value system, also called positional system: system where the same digits could be re-used to mean different values

Babylonians also had the base of 60, while Egyptians can be said to have a base of 10 (but not as part of a positional system)

Egyptians, however, unlike Babylonians, had the concept and a number for 0.