Thursday, September 13, 2012

649

649 = 11 x 59.

649 is a semiprime whose digits are each a semiprime (A107342).

649 is the smallest number n so that n2 is 1 more than 13 times a square: 6492 = 1 + 13(180)2.

649 is 345 in base 14.

649 is a brilliant number (A078972).


Gliese 649 is a red dwarf star in the constellation of Hercules.

Source: What's Special About This Number?

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