128

This number is a composite.

+ 128 = 2! + 3! + 5!. [Petersen]

+ 128 + (1 + 2 + 8) is prime. Note that 1 * 2 * 8 divides 128. [Capelle]

+ The largest known even number that can be expressed as the sum of two primes in exactly three ways. [Capelle]

+ Smallest positive integer k>=2 such that no primes of the form (k-1)*k^n-1, with positive integer n, are known. [Luen]

+ Are 127 and 131 the largest cousin primes with a power of two (128) between them? [Gaydos]

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