257365 has 4 divisors (see below), whose sum is σ = 308844. Its totient is φ = 205888.

The previous prime is 257353. The next prime is 257371. The reversal of 257365 is 563752.

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 62001 + 195364 = 249^2 + 442^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257365 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25732 + ... + 25741.

It is an arithmetic number, because the mean of its divisors is an integer number (77211).

2²⁵⁷³⁶⁵ is an apocalyptic number.

It is an amenable number.

257365 is a deficient number, since it is larger than the sum of its proper divisors (51479).

257365 is an equidigital number, since it uses as much as digits as its factorization.

257365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51478.

The product of its digits is 6300, while the sum is 28.

The square root of 257365 is about 507.3115413629. The cubic root of 257365 is about 63.6086963835.

The spelling of 257365 in words is "two hundred fifty-seven thousand, three hundred sixty-five".