Simon Singh continues his Five Numbers series on BBC 4 Radio:

This time Singh explores 1 (the most popular), 2, 6 (the pivot), 6.67 x 10^-11 (or G), and 1729 (the first of the “Ramanujan numbers”).

Probably best to start with the original Five Numbers series if you've not heard them, covering Zero, Pi, the Golden Ratio, the imaginary 'i', and Infinity.

The first programme of the new series A Further Five Numbers all available for listening now.

Via the Unreasonable Man.