257457 has 4 divisors (see below), whose sum is σ = 343280. Its totient is φ = 171636.

The previous prime is 257447. The next prime is 257459. The reversal of 257457 is 754752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 257457 - 2¹² = 253361 is a prime.

It is a D-number.

It is a Duffinian number.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (257459) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42907 + ... + 42912.

It is an arithmetic number, because the mean of its divisors is an integer number (85820).

2²⁵⁷⁴⁵⁷ is an apocalyptic number.

It is an amenable number.

257457 is a deficient number, since it is larger than the sum of its proper divisors (85823).

257457 is an equidigital number, since it uses as much as digits as its factorization.

257457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85822.

The product of its digits is 9800, while the sum is 30.

The square root of 257457 is about 507.4022073267. The cubic root of 257457 is about 63.6162748588.

It can be divided in two parts, 25745 and 7, that added together give a palindrome (25752).

The spelling of 257457 in words is "two hundred fifty-seven thousand, four hundred fifty-seven".