This number is a composite.

+ 345*2^345 - 345 - 2^345 is prime. [Noll]

+ 3!+4!+5! plus one is a palindromic prime . It is the smallest 3-digit number of this form, with consecutive digits in ascending order. [Bajpai]

+ 345 is the sum of the first 6 Fibonacci primes. [Honaker]

+ The first 345 digits in decimal expansion of tau form a prime, where tau = 2π. [Bajpai]

(There is one curio for this number that has not yet been approved by an editor.)

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