256585697 has 2 divisors, whose sum is σ = 256585698. Its totient is φ = 256585696.

The previous prime is 256585691. The next prime is 256585699. The reversal of 256585697 is 796585652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 256512256 + 73441 = 16016^2 + 271^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256585697 is a prime.

Together with 256585699, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (256585691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128292848 + 128292849.

It is an arithmetic number, because the mean of its divisors is an integer number (128292849).

Almost surely, 2^256585697 is an apocalyptic number.

It is an amenable number.

256585697 is a deficient number, since it is larger than the sum of its proper divisors (1).

256585697 is an equidigital number, since it uses as much as digits as its factorization.

256585697 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536000, while the sum is 53.

The square root of 256585697 is about 16018.2925744288. The cubic root of 256585697 is about 635.4442894814. Note that the first 3 decimals are identical.

The spelling of 256585697 in words is "two hundred fifty-six million, five hundred eighty-five thousand, six hundred ninety-seven".