Problems & Puzzles: Puzzles

Puzzle 26.- Honaker & Jud. McCranie puzzle

"30103 is the only known multi-digit palindromic prime found by averaging the divisors of a composite number. [McCranie and Honaker, July 1998]

By the way they have found two solutions:

30103 = average divisors of (149645) and

30103 = average divisors of (179574)

The divisors of 149645 are 1, 5, 173, 865, 29929, and 149645.

30103 = (1+ 5+173+ 865+ 29929+149645)/6

The divisors of 179574 are 1, 2, 3, 6, 173, 346, 519, 1038, 29929,

59858, 89787, and 179574.

30103 = (1+ 2+ 3+ 6+ 173+ 346+ 519+ 1038+ 29929+59858+ 89787+179574)/12

Question : Can the average of the divisors of other composite number to produce another pal-prime ?


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