256973869 has 2 divisors, whose sum is σ = 256973870. Its totient is φ = 256973868.

The previous prime is 256973861. The next prime is 256973909. The reversal of 256973869 is 968379652.

256973869 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149084100 + 107889769 = 12210^2 + 10387^2 .

It is a cyclic number.

It is not a de Polignac number, because 256973869 - 2³ = 256973861 is a prime.

It is a super-2 number, since 2×256973869² = 132071138697658322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256973861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128486934 + 128486935.

It is an arithmetic number, because the mean of its divisors is an integer number (128486935).

Almost surely, 2^256973869 is an apocalyptic number.

It is an amenable number.

256973869 is a deficient number, since it is larger than the sum of its proper divisors (1).

256973869 is an equidigital number, since it uses as much as digits as its factorization.

256973869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 55.

The square root of 256973869 is about 16030.4045176658. The cubic root of 256973869 is about 635.7645689589.

The spelling of 256973869 in words is "two hundred fifty-six million, nine hundred seventy-three thousand, eight hundred sixty-nine".