256975897 has 2 divisors, whose sum is σ = 256975898. Its totient is φ = 256975896.

The previous prime is 256975891. The next prime is 256975921. The reversal of 256975897 is 798579652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 174874176 + 82101721 = 13224^2 + 9061^2 .

It is a cyclic number.

It is not a de Polignac number, because 256975897 - 2³ = 256975889 is a prime.

It is a super-2 number, since 2×256975897² = 132073223277909218, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (256975891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128487948 + 128487949.

It is an arithmetic number, because the mean of its divisors is an integer number (128487949).

Almost surely, 2^256975897 is an apocalyptic number.

It is an amenable number.

256975897 is a deficient number, since it is larger than the sum of its proper divisors (1).

256975897 is an equidigital number, since it uses as much as digits as its factorization.

256975897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9525600, while the sum is 58.

The square root of 256975897 is about 16030.4677723390. The cubic root of 256975897 is about 635.7662414081.

The spelling of 256975897 in words is "two hundred fifty-six million, nine hundred seventy-five thousand, eight hundred ninety-seven".