This number is a composite.

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

+ 18 is the only two-digit number m , such that three numbers, m + prime(m), m^2 + prime(m^2) & m^3 + prime(m^3), are primes. [Firoozbakht]

+ 18 = π(81-18). The only number with this property. [Firoozbakht]

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