256685669 has 8 divisors (see below), whose sum is σ = 273927168. Its totient is φ = 239682240.

The previous prime is 256685647. The next prime is 256685719. The reversal of 256685669 is 966586652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256685669 is a prime.

It is a super-2 number, since 2×256685669² = 131775065339955122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256685669.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256685629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57287 + ... + 61604.

It is an arithmetic number, because the mean of its divisors is an integer number (34240896).

Almost surely, 2^256685669 is an apocalyptic number.

It is an amenable number.

256685669 is a deficient number, since it is larger than the sum of its proper divisors (17241499).

256685669 is a wasteful number, since it uses less digits than its factorization.

256685669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 119035.

The product of its digits is 4665600, while the sum is 53.

The square root of 256685669 is about 16021.4128278376. The cubic root of 256685669 is about 635.5268069255.

The spelling of 256685669 in words is "two hundred fifty-six million, six hundred eighty-five thousand, six hundred sixty-nine".