257109 has 4 divisors (see below), whose sum is σ = 342816. Its totient is φ = 171404.

The previous prime is 257107. The next prime is 257123. The reversal of 257109 is 901752.

257109 = 165² + 166² + ... + 173².

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 257109 - 2¹ = 257107 is a prime.

It is a super-2 number, since 2×257109² = 132210075762, which contains 22 as substring.

It is a D-number.

It is a Curzon number.

It is a plaindrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42849 + ... + 42854.

It is an arithmetic number, because the mean of its divisors is an integer number (85704).

2²⁵⁷¹⁰⁹ is an apocalyptic number.

It is an amenable number.

257109 is a deficient number, since it is larger than the sum of its proper divisors (85707).

257109 is an equidigital number, since it uses as much as digits as its factorization.

257109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85706.

The product of its (nonzero) digits is 630, while the sum is 24.

The square root of 257109 is about 507.0591681451. The cubic root of 257109 is about 63.5875989428.

The spelling of 257109 in words is "two hundred fifty-seven thousand, one hundred nine".