257723 has 4 divisors (see below), whose sum is σ = 266640. Its totient is φ = 248808.

The previous prime is 257717. The next prime is 257731. The reversal of 257723 is 327752.

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 257723 - 2⁴ = 257707 is a prime.

It is a super-2 number, since 2×257723² = 132842289458, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 257692 and 257701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257713) 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, 4415 + ... + 4472.

It is an arithmetic number, because the mean of its divisors is an integer number (66660).

2²⁵⁷⁷²³ is an apocalyptic number.

257723 is a deficient number, since it is larger than the sum of its proper divisors (8917).

257723 is an equidigital number, since it uses as much as digits as its factorization.

257723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8916.

The product of its digits is 2940, while the sum is 26.

The square root of 257723 is about 507.6642591320. The cubic root of 257723 is about 63.6381763862.

The spelling of 257723 in words is "two hundred fifty-seven thousand, seven hundred twenty-three".