I picked this one up thinking it would be a math history book (and because it had a great cover!), but it turned out to be more of a math book. Which would have been fine if I had ever taken advanced number theory or electrical engineering courses, but I hadn't. Still, I broke out my calculus textbook and followed along as best I could. Probably absorbed 60% of it. When writing prose instead of formulas, the author is witty and engaging. I'd like to read a pure history of math book by him.