Leibniz was the first thing I thought - IIRC he and Newton basically "invented the calculus" simultaneously and independent of each other. But my stars, Newton's contributions to astronomy, optics, oobleck and fig-based treats put him a cut above :)

Da Vinci is somehow underrated here. The Codex Leicester with bike planes &c, probably in Gates' bathroom, and also he was somehow involved in the invention of double-entry accounting. What didn't Leo touch?

Benjamin Franklin, boy, that guy. The US, electricity. Bifocals. Franklin stove. Discovered the gulf stream. You can still go to where Ben puked in the Haymarket and occasionally rewrote TJ's little declaration of something or another.

BUT - the sleeper here is Thales of Miletus. The first true pre-Socratic philosopher, got into theories about electricity among other things as part of spurning mythology in lieu of science, credited with "know thyself", math that led to the school of Pythagoras (via Anaximander), and I think he invented venture capital by investing in other's olive presses for a tribute.