## Thursday, April 29, 2010

### 648

648 = 23 x 34 = 12 x 23 x 34.

648 has a representation as a sum of two squares: 648 = 182 + 182.

648 is the smallest number whose decimal part of its 6th root begins with the digits 1 to 9 in some order: 2.941682753. . . .

6483 = 272,097,792 = (-27 - 20 - 97 + 792)3.

648 is 220000 in base 3, 22020 in base 4, 3000 in base 6, 800 in base 9, and 200 in base 18.

EgyptAir Flight 648 was a Boeing 737-200 airliner hijacked in 1985 by the terrorist Abu Nadal Organization.

#### 1 comment:

Anonymous said...

One of my favorite numbers is 648 (which is missing in The Penguin Dictionary of Curious and Interesting Numbers).

Some its properties:

64*8 = 512 +
64/8 = 8 +
64+8 = 72 +
64-8 = 56 =
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648
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648 = 16² - 17² + 18² + ... + 30² - 31² + 32² = -33² + 34² - 35² + ... + 46² - 47² + 48².

648 = 83² - 79², where 83 and 79 are consecutive primes.

648 = 101 + 547, where 101 = prime(26) and 547 = prime(prime(26)).

648 / (6+4+8) is a square (36).

648 divides 53^6-1.

Also, 648 is an Abundant number, Odious number, Smith number, Practical number, Powerful number.