30103
30103 is the only known multi-digit palindromic prime found by averaging the divisors of a composite number.for example:
divisors of 149645:1, 5, 173, 865, 29929, 149645
averaging the divisors of 149645 is :
(1+ 5+173+ 865+ 29929+149645)/6=30103.
divisors of 179574:
1, 2, 3, 6, 173, 346, 519, 1038, 29929,59858, 89787, 179574.
averaging the divisors of 149645 is :
(1+ 2+ 3+ 6+ 173+ 346+ 519+ 1038+ 29929+59858+ 89787+179574)/12=30103.
Question : Can the average of the divisors of other composite number to produce another pal-prime ? 困难的很 似乎除了穷举没有别的办法
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