This number is a prime.

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

+ The only prime p such that p times reversal(p) - 1 is prime. [Firoozbakht]

+ The only known number n such that the sum of the proper divisors of n is equal to phi(n). [Firoozbakht]

+ Only prime whose sum of divisors is prime. [Firoozbakht]

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