According to G.H. Hardy (English mathematician 01877-01947), the number

1729is the "smallest number expressible as the sum of two cubes in two different ways."1729= 1^3 + 12^3 ...and...1729= 9^3 + 10^3Masahiko Funiwara (Japanese mathematician) showed that "

1729is one of four natural numbers (the others are81and1458and the trivial case1) which, when its digits are added together, produces a sum which, when multiplied by its reversed self, yields the original number."1 + 7 + 2 + 9 = 19 19 * 91 = 1729## Update::2015.10.15

Phys.org::Mathematicians find 'magic key' to drive Ramanujan's taxi-cab number

"Srinivasa Ramanujan, who had an uncanny sense for the idiosyncratic properties of numbers, somehow knew that1729can be represented as 1 cubed + 12 cubed and 9 cubed + 10 cubed, and no smaller positive number can be written in two such ways." -- Phys.org

**Creator:** Gerald Thurman
[gthurman@gmail.com]

**Created:** 19 December 2007

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