WON TOPIC 59

World!Of Numbers		WON plate 59 \|
[ August 12, 1999 ] One of a kind palindrome 21312 *Palindrome* 21312 is another unique one when taken into consideration the following two rules : First, the digit zero may not appear in the palindrome Secondly, the sum of its digits equals the number of its prime factors 21312 = 2 + 1 + 3 + 1 + 2 = 9 so there should exist nine prime factors ! Indeed as 21312 = 2 x 2 x 2 x 2 x 2 x 2 x 3 x 3 x 37. Dear puzzlers, proof me wrong by finding a second solution... P.S. 21312 is also the largest substring in 2⁴⁹ or 562949953421312 ( A046260 ) (Note for the insiders : 21312 equals 32 times the number of the beast 666!)
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