257663 has 4 divisors (see below), whose sum is σ = 294480. Its totient is φ = 220848.

The previous prime is 257657. The next prime is 257671. The reversal of 257663 is 366752.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 257663 - 2⁸ = 257407 is a prime.

It is a Duffinian number.

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 257663.

It is not an unprimeable number, because it can be changed into a prime (257263) 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, 18398 + ... + 18411.

It is an arithmetic number, because the mean of its divisors is an integer number (73620).

2²⁵⁷⁶⁶³ is an apocalyptic number.

257663 is a deficient number, since it is larger than the sum of its proper divisors (36817).

257663 is an equidigital number, since it uses as much as digits as its factorization.

257663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36816.

The product of its digits is 7560, while the sum is 29.

The square root of 257663 is about 507.6051615183. The cubic root of 257663 is about 63.6332375088.

The spelling of 257663 in words is "two hundred fifty-seven thousand, six hundred sixty-three".