809860 has 12 divisors (see below), whose sum is σ = 1700748. Its totient is φ = 323936.

The previous prime is 809843. The next prime is 809869. The reversal of 809860 is 68908.

It can be written as a sum of positive squares in 2 ways, for example, as 173056 + 636804 = 416^2 + 798^2 .

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, 20227 + ... + 20266.

It is an arithmetic number, because the mean of its divisors is an integer number (141729).

2⁸⁰⁹⁸⁶⁰ is an apocalyptic number.

It is an amenable number.

809860 is an abundant number, since it is smaller than the sum of its proper divisors (890888).

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

809860 is a wasteful number, since it uses less digits than its factorization.

809860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40502 (or 40500 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 809860 is about 899.9222188612. The cubic root of 809860 is about 93.2116043439.

Subtracting from 809860 its product of nonzero digits (3456), we obtain a square (806404 = 898²).

The spelling of 809860 in words is "eight hundred nine thousand, eight hundred sixty".