484
This number is a composite.
sigma(484) = prime(4)*prime(8)*prime(4). 484 is the largest known (up to 10^8) such number. [Firoozbakht]
π(484) = phi(484)-4*8*4. [Firoozbakht]
(68*10^484+7)/3 is prime. [Pankajjyoti]
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