"The Man Who Knew Infinity" by Robert Kanigel on Ramanujan is good. "Georg Cantor" by Joseph Dauben is dense but interesting; it is closer to a mathematical tr

"The Man Who Knew Infinity" by Robert Kanigel on Ramanujan is good. "Georg Cantor" by Joseph Dauben is dense but interesting; it is closer to a mathematical treatment of Cantor's works than a biographical one. Some experience with the basics of analysis would be beneficial, but a surprising amount is developed throughout the book.