>>> Testing new web page format problems? suggestions?
87 = 22 + 32 + 52 + 72. [Sladcik]
87 is the largest number that yields a prime when any of the one-digit primes 2, 5 or 7 is inserted between any two digits. The only other such number is 27 (and trivially, the 1 digit numbers). [Hasler]
(There are 3 curios for this number that have not yet been approved by an editor.)
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