99

This number is a composite.

Just showing those entries submitted by 'Firoozbakht': (Click here to show all)

+ 99 = π( prime(9)*prime(9) ). Note that 99 is the only two-digit number with this property. [Firoozbakht]

+ 99!/π(99)! + 1 is prime. [Firoozbakht]

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