93

This number is a composite.

+ The first 93 digits of 93! form a prime number. [Vrba]

+ The exact number of 5-digit palindromic primes. [Patterson]

+ (93!/39!)+1 is prime. [Patterson]

+ The least positive integer that produces exactly 93 primes in a Collatz trajectory has never been found.

+ The 93 rightmost decimal digits of Graham's number form a prime. [Daniels]

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

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