Per Wikipedia, he published 40 novels and over 280 non-fiction books. He's best known for SF but he certainly didn't spend his whole career on it.

> He's best known for SF but he certainly didn't spend his whole career on it.

Indeed after becoming a giant of the field in the 1940s and 1950s, when he wrote most of the novels and short stories we know him for (Robots, Foundation and Empire) he took a long hiatus. In the 1960s and 70s, as far as I can tell, his meager sci-fi output consisted of some short stories, a couple of novelizations of sci-fi movies, and a standalone novel (The Gods Themselves).

After Sputnik he focused on science writing, believing that to be more widely useful.

He only returned to writing more Foundation, Robots, and Empire novels in the 1980s.