866959 has 4 divisors (see below), whose sum is σ = 868840. Its totient is φ = 865080.

The previous prime is 866953. The next prime is 866963. The reversal of 866959 is 959668.

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 866959 - 2⁵ = 866927 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 (866953) 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, 277 + ... + 1345.

It is an arithmetic number, because the mean of its divisors is an integer number (217210).

2⁸⁶⁶⁹⁵⁹ is an apocalyptic number.

866959 is a deficient number, since it is larger than the sum of its proper divisors (1881).

866959 is a wasteful number, since it uses less digits than its factorization.

866959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1880.

The product of its digits is 116640, while the sum is 43.

The square root of 866959 is about 931.1063311996. The cubic root of 866959 is about 95.3526688521.

The spelling of 866959 in words is "eight hundred sixty-six thousand, nine hundred fifty-nine".