Wednesday, August 22, 2012

1521

1521 = 3 x 3 x 13 x 13.

1521 is a perfect square: 1521 = 392.

1521 is the smallest number that can be written as the sum of four distinct cubes in three ways: 1521 = 113 + 53 + 43 + 13 = 103 + 83 + 23 + 13 = 93 + 83 + 63 + 43.

1521 has a representation as a sum of two squares: 1521 = 152 + 362.

1521 is a divisor of 223 - 1.

1521 is a centered octagonal number.


Source: What's Special About This Number?

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