257749 has 4 divisors (see below), whose sum is σ = 261664. Its totient is φ = 253836.

The previous prime is 257731. The next prime is 257783. The reversal of 257749 is 947752.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 257749 - 2⁵ = 257717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257249) 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 3 ways as a sum of consecutive naturals, for example, 1857 + ... + 1990.

It is an arithmetic number, because the mean of its divisors is an integer number (65416).

2²⁵⁷⁷⁴⁹ is an apocalyptic number.

It is an amenable number.

257749 is a deficient number, since it is larger than the sum of its proper divisors (3915).

257749 is an equidigital number, since it uses as much as digits as its factorization.

257749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3914.

The product of its digits is 17640, while the sum is 34.

The square root of 257749 is about 507.6898659615. The cubic root of 257749 is about 63.6403163284.

The spelling of 257749 in words is "two hundred fifty-seven thousand, seven hundred forty-nine".