1136972771
This number is a composite.
1136972771 = 11 * 31 * 71 * 151 * 311 is a Zeisel Number because its five prime factors are consecutive elements of the linear recurrence prime(i+1) = 2*prime(i) + 9. Curiously, all of those prime factors are either palindromes or emirps, since 11, 13, 17, 151, and 113 are primes. Note that 1136972771 right-truncates to the prime 11369 and then 113 (the digit reversal of one of its factors), and left-truncates to the prime 71 (one of its factors). [Post]
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