256406571 has 12 divisors (see below), whose sum is σ = 370832280. Its totient is φ = 170722080.

The previous prime is 256406537. The next prime is 256406617. The reversal of 256406571 is 175604652.

It is a happy number.

256406571 is a `hidden beast` number, since 2 + 5 + 640 + 6 + 5 + 7 + 1 = 666.

256406571 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 256406571 - 2⁷ = 256406443 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (256406471) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10266 + ... + 24863.

It is an arithmetic number, because the mean of its divisors is an integer number (30902690).

Almost surely, 2^256406571 is an apocalyptic number.

256406571 is a deficient number, since it is larger than the sum of its proper divisors (114425709).

256406571 is a wasteful number, since it uses less digits than its factorization.

256406571 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35946 (or 35943 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The square root of 256406571 is about 16012.7003031968. The cubic root of 256406571 is about 635.2963842618.

The spelling of 256406571 in words is "two hundred fifty-six million, four hundred six thousand, five hundred seventy-one".