99

+ There are 9 ways to express 99 as p + 2q, where p and q are prime. [Hodges]

+ The 99th prime plus (9+9) is the next prime.

+ 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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