257897 has 4 divisors (see below), whose sum is σ = 266820. Its totient is φ = 248976.

The previous prime is 257893. The next prime is 257903. The reversal of 257897 is 798752.

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

It can be written as a sum of positive squares in 2 ways, for example, as 80656 + 177241 = 284^2 + 421^2 .

It is a cyclic number.

It is not a de Polignac number, because 257897 - 2² = 257893 is a prime.

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 257897.

It is not an unprimeable number, because it can be changed into a prime (257893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4418 + ... + 4475.

It is an arithmetic number, because the mean of its divisors is an integer number (66705).

2²⁵⁷⁸⁹⁷ is an apocalyptic number.

It is an amenable number.

257897 is a deficient number, since it is larger than the sum of its proper divisors (8923).

257897 is an equidigital number, since it uses as much as digits as its factorization.

257897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8922.

The product of its digits is 35280, while the sum is 38.

The square root of 257897 is about 507.8356033206. The cubic root of 257897 is about 63.6524947974.

The spelling of 257897 in words is "two hundred fifty-seven thousand, eight hundred ninety-seven".