809864 has 16 divisors (see below), whose sum is σ = 1656720. Its totient is φ = 368080.

The previous prime is 809843. The next prime is 809869. The reversal of 809864 is 468908.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 809864.

It is not an unprimeable number, because it can be changed into a prime (809869) 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, 4514 + ... + 4689.

It is an arithmetic number, because the mean of its divisors is an integer number (103545).

2⁸⁰⁹⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

809864 is an abundant number, since it is smaller than the sum of its proper divisors (846856).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

809864 is a wasteful number, since it uses less digits than its factorization.

809864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9220 (or 9216 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 809864 is about 899.9244412727. The cubic root of 809864 is about 93.2117578049.

The spelling of 809864 in words is "eight hundred nine thousand, eight hundred sixty-four".