257345 has 8 divisors (see below), whose sum is σ = 336960. Its totient is φ = 187120.

The previous prime is 257339. The next prime is 257351. The reversal of 257345 is 543752.

It is an interprime number because it is at equal distance from previous prime (257339) and next prime (257351).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 257345 - 2⁶ = 257281 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2285 + ... + 2394.

It is an arithmetic number, because the mean of its divisors is an integer number (42120).

2²⁵⁷³⁴⁵ is an apocalyptic number.

It is an amenable number.

257345 is a deficient number, since it is larger than the sum of its proper divisors (79615).

257345 is a wasteful number, since it uses less digits than its factorization.

257345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4695.

The product of its digits is 4200, while the sum is 26.

The square root of 257345 is about 507.2918292265. The cubic root of 257345 is about 63.6070486498.

The spelling of 257345 in words is "two hundred fifty-seven thousand, three hundred forty-five".