256535869 has 2 divisors, whose sum is σ = 256535870. Its totient is φ = 256535868.

The previous prime is 256535861. The next prime is 256535879. The reversal of 256535869 is 968535652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 143113369 + 113422500 = 11963^2 + 10650^2 .

It is a cyclic number.

It is not a de Polignac number, because 256535869 - 2³ = 256535861 is a prime.

It is a super-2 number, since 2×256535869² = 131621304167170322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256535861) 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, 128267934 + 128267935.

It is an arithmetic number, because the mean of its divisors is an integer number (128267935).

Almost surely, 2^256535869 is an apocalyptic number.

It is an amenable number.

256535869 is a deficient number, since it is larger than the sum of its proper divisors (1).

256535869 is an equidigital number, since it uses as much as digits as its factorization.

256535869 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1944000, while the sum is 49.

The square root of 256535869 is about 16016.7371521168. The cubic root of 256535869 is about 635.4031531693.

The spelling of 256535869 in words is "two hundred fifty-six million, five hundred thirty-five thousand, eight hundred sixty-nine".