256257 has 8 divisors (see below), whose sum is σ = 379680. Its totient is φ = 170820.

The previous prime is 256219. The next prime is 256279. The reversal of 256257 is 752652.

It is not a de Polignac number, because 256257 - 2⁷ = 256129 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 9491 = 256257 / (2 + 5 + 6 + 2 + 5 + 7).

It is a self number, because there is not a number n which added to its sum of digits gives 256257.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 256257.

It is not an unprimeable number, because it can be changed into a prime (256057) 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, 4719 + ... + 4772.

It is an arithmetic number, because the mean of its divisors is an integer number (47460).

2²⁵⁶²⁵⁷ is an apocalyptic number.

256257 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

256257 is a deficient number, since it is larger than the sum of its proper divisors (123423).

256257 is an equidigital number, since it uses as much as digits as its factorization.

256257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9500 (or 9494 counting only the distinct ones).

The product of its digits is 4200, while the sum is 27.

The square root of 256257 is about 506.2183323429. The cubic root of 256257 is about 63.5172829968.

The spelling of 256257 in words is "two hundred fifty-six thousand, two hundred fifty-seven".