255917 has 2 divisors, whose sum is σ = 255918. Its totient is φ = 255916.

The previous prime is 255907. The next prime is 255919. The reversal of 255917 is 719552.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 244036 + 11881 = 494^2 + 109^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-255917 is a prime.

Together with 255919, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 255917.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 255917.

It is not a weakly prime, because it can be changed into another prime (255919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 127958 + 127959.

It is an arithmetic number, because the mean of its divisors is an integer number (127959).

2²⁵⁵⁹¹⁷ is an apocalyptic number.

It is an amenable number.

255917 is a deficient number, since it is larger than the sum of its proper divisors (1).

255917 is an equidigital number, since it uses as much as digits as its factorization.

255917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3150, while the sum is 29.

The square root of 255917 is about 505.8823974008. The cubic root of 255917 is about 63.4891791345.

The spelling of 255917 in words is "two hundred fifty-five thousand, nine hundred seventeen".