The Man Who Loved Only Numbers is a biography of the famous mathematician Paul Erdős written by Paul Hoffman. The book was first published on July 15, 1998, by Hyperion Books as a hardcover edition. A paperback edition appeared in 1999. The book is, in the words of the author, "a work in oral history based on the recollections of Erdős, his collaborators and their spouses". The book was a bestseller in the United Kingdom and has been published in 15 different languages. The book won the 1999 Rhône-Poulenc Prize, beating many distinguished and established writers, including E. O. Wilson.

Paul Erdős was a Hungarian mathematician. He was one of the most prolific mathematicians and producers of mathematical conjectures of the 20th century. Erdős pursued and proposed problems in discrete mathematics, graph theory, number theory, mathematical analysis, approximation theory, set theory, and probability theory. Much of his work centered around discrete mathematics, cracking many previously unsolved problems in the field. He championed and contributed to Ramsey theory, which studies the conditions in which order necessarily appears. Overall, his work leaned towards solving previously open problems, rather than developing or exploring new areas of mathematics.