Friday, June 25, 2010

818

818 = 2 x 409.

818 is the smallest palindrome that can be expressed as the sum of the squares of two primes: 818 = 172 + 232.

818 is the only three-digit tetradic integer such that the sum of the differences of the number and each digit raised to the digit is prime: (818 - 8)8 + (818 - 1)1 + (818 - 8)8 = 370604037770368200000817, a prime.

818 is the number of ways to dissect a 12-gon using non-crossing diagonals into polygons with an even number of sides.

818 is the telephone area code for the San Fernando Valley, California.

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