256957 has 2 divisors, whose sum is σ = 256958. Its totient is φ = 256956.

The previous prime is 256939. The next prime is 256967. The reversal of 256957 is 759652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 241081 + 15876 = 491^2 + 126^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256957 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128478 + 128479.

It is an arithmetic number, because the mean of its divisors is an integer number (128479).

2²⁵⁶⁹⁵⁷ is an apocalyptic number.

It is an amenable number.

256957 is a deficient number, since it is larger than the sum of its proper divisors (1).

256957 is an equidigital number, since it uses as much as digits as its factorization.

256957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18900, while the sum is 34.

The square root of 256957 is about 506.9092620973. The cubic root of 256957 is about 63.5750657107.

The spelling of 256957 in words is "two hundred fifty-six thousand, nine hundred fifty-seven".