866257 has 8 divisors (see below), whose sum is σ = 1011456. Its totient is φ = 726432.

The previous prime is 866231. The next prime is 866279. The reversal of 866257 is 752668.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-866257 is a prime.

It is a Duffinian number.

866257 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (866057) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 988 + ... + 1645.

It is an arithmetic number, because the mean of its divisors is an integer number (126432).

2⁸⁶⁶²⁵⁷ is an apocalyptic number.

It is an amenable number.

866257 is a deficient number, since it is larger than the sum of its proper divisors (145199).

866257 is a wasteful number, since it uses less digits than its factorization.

866257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2687.

The product of its digits is 20160, while the sum is 34.

The square root of 866257 is about 930.7292839489. The cubic root of 866257 is about 95.3269253630.

The spelling of 866257 in words is "eight hundred sixty-six thousand, two hundred fifty-seven".