One of the only types of nonfiction I enjoy reading is biographies of people who have done impressive stuff in fields I'm interested in. That's why I've got this shelf of books about Shakespeare, Einstein, Jobs, Feynman and the like. One of my favorite of the bunch is The Man Who Loved Only Numbers, by Paul Hoffman, a biography of Paul Erdos.
Erdos fascinated me more and more as I studied mathematics because of both how prolific he was, and how collaborative. The book tells the story not just of how his life was shaped by his drive to continually do more math, with more people, but how those peoples' lives were frequently shaped by interacting with Erdos. Erdos published over 1500 articles, with more than 500 collaborators during his life.
I think that it's important to read biographies like this to remind ourselves that it's not a requirement of the "hard sciences" that they be researched in isolation, and that some of the most amazing people in their fields are frequently amazing for other reasons as well. Perhaps more topically to Brilliant, Erdos strongly believed in cultivating young mathematical talent, and while he had no children of his own, mentored many children over the phone and through the mail.
While not the only biography of Erdos, it's my favorite. It's a fun, quick read that has enough personal anecdotes to make you feel connected to the subject, and enough math content to keep that angle interesting as well.