256685711 has 4 divisors (see below), whose sum is σ = 257836992. Its totient is φ = 255534432.

The previous prime is 256685647. The next prime is 256685719. The reversal of 256685711 is 117586652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256685711 - 2⁶ = 256685647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256685719) 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 in 3 ways as a sum of consecutive naturals, for example, 575306 + ... + 575751.

It is an arithmetic number, because the mean of its divisors is an integer number (64459248).

Almost surely, 2^256685711 is an apocalyptic number.

256685711 is a deficient number, since it is larger than the sum of its proper divisors (1151281).

256685711 is a wasteful number, since it uses less digits than its factorization.

256685711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1151280.

The product of its digits is 100800, while the sum is 41.

The square root of 256685711 is about 16021.4141385834. The cubic root of 256685711 is about 635.5268415881.

The spelling of 256685711 in words is "two hundred fifty-six million, six hundred eighty-five thousand, seven hundred eleven".