In Number Freak (Perigee Books, 2009), Derrick Niederman tells the stories behind the numerals 1 to 200. Each number gets an entry, detailing its significance from ancient myth to mathematical reality. For instance, the prime number 17 is considered unlucky in Italy and was detested by the Pythagoreans compared with its neighbours 16 and 18; yet the choreographer George Balanchine saw its beauty in a double-diamond configuration of 17 dancers in his ballet Serenade.

An intimate view of mentorship is revealed by US mathematician Steven Strogatz in The Calculus of Friendship (Princeton University Press, 2009), a compilation of letters exchanged with his high-school maths teacher over 30 years. Through their correspondence they share problems in calculus, chaos theory and major life events, from professional and sporting successes to family bereavements and divorce. The book touchingly charts their changing roles and relationship, from student to professor, teacher to retirement.

Numerous contacts with neighbours or workmates have a profound effect on our success, happiness and health, according to journalist Melinda Blau and psychologist Karen Fingerman. In Consequential Strangers (W. W. Norton, 2009), they explain how casual acquaintances are most likely to tip you off about a new job or provide a creative solution to a problem. Even though wide social networks can encourage bullying, lying and gossip, they enable people to become more conscious of their shared humanity.