257397 has 24 divisors (see below), whose sum is σ = 426816. Its totient is φ = 137088.

The previous prime is 257381. The next prime is 257399. The reversal of 257397 is 793752.

It is not a de Polignac number, because 257397 - 2⁴ = 257381 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257399) 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 23 ways as a sum of consecutive naturals, for example, 2448 + ... + 2550.

It is an arithmetic number, because the mean of its divisors is an integer number (17784).

2²⁵⁷³⁹⁷ is an apocalyptic number.

It is an amenable number.

257397 is a deficient number, since it is larger than the sum of its proper divisors (169419).

257397 is a wasteful number, since it uses less digits than its factorization.

257397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137 (or 130 counting only the distinct ones).

The product of its digits is 13230, while the sum is 33.

The square root of 257397 is about 507.3430791880. The cubic root of 257397 is about 63.6113325797.

The spelling of 257397 in words is "two hundred fifty-seven thousand, three hundred ninety-seven".