257617 has 4 divisors (see below), whose sum is σ = 261220. Its totient is φ = 254016.

The previous prime is 257611. The next prime is 257627. The reversal of 257617 is 716752.

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

It can be written as a sum of positive squares in 2 ways, for example, as 77841 + 179776 = 279^2 + 424^2 .

It is a cyclic number.

It is not a de Polignac number, because 257617 - 2⁷ = 257489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257611) 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, 1692 + ... + 1837.

It is an arithmetic number, because the mean of its divisors is an integer number (65305).

257617 is a Friedman number, since it can be written as 7^6+(5+1)^7/2, using all its digits and the basic arithmetic operations.

2²⁵⁷⁶¹⁷ is an apocalyptic number.

It is an amenable number.

257617 is a deficient number, since it is larger than the sum of its proper divisors (3603).

257617 is an equidigital number, since it uses as much as digits as its factorization.

257617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3602.

The product of its digits is 2940, while the sum is 28.

The square root of 257617 is about 507.5598486878. The cubic root of 257617 is about 63.6294505168.

The spelling of 257617 in words is "two hundred fifty-seven thousand, six hundred seventeen".