257943 has 16 divisors (see below), whose sum is σ = 400896. Its totient is φ = 144480.

The previous prime is 257921. The next prime is 257947. The reversal of 257943 is 349752.

It is not a de Polignac number, because 257943 - 2⁶ = 257879 is a prime.

257943 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 257943.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 257943.

It is not an unprimeable number, because it can be changed into a prime (257947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1405 + ... + 1577.

It is an arithmetic number, because the mean of its divisors is an integer number (25056).

2²⁵⁷⁹⁴³ is an apocalyptic number.

257943 is a deficient number, since it is larger than the sum of its proper divisors (142953).

257943 is a wasteful number, since it uses less digits than its factorization.

257943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254.

The product of its digits is 7560, while the sum is 30.

The square root of 257943 is about 507.8808915484. The cubic root of 257943 is about 63.6562790481.

Subtracting 257943 from its reverse (349752), we obtain a square (91809 = 303²).

The spelling of 257943 in words is "two hundred fifty-seven thousand, nine hundred forty-three".