866089 has 4 divisors (see below), whose sum is σ = 989824. Its totient is φ = 742356.

The previous prime is 866087. The next prime is 866093. The reversal of 866089 is 980668.

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 866089 - 2¹ = 866087 is a prime.

It is a super-2 number, since 2×866089² = 1500220311842, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866081) 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, 61857 + ... + 61870.

It is an arithmetic number, because the mean of its divisors is an integer number (247456).

2⁸⁶⁶⁰⁸⁹ is an apocalyptic number.

It is an amenable number.

866089 is a deficient number, since it is larger than the sum of its proper divisors (123735).

866089 is a wasteful number, since it uses less digits than its factorization.

866089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123734.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 866089 is about 930.6390277653. The cubic root of 866089 is about 95.3207624657.

The spelling of 866089 in words is "eight hundred sixty-six thousand, eighty-nine".