809020 has 24 divisors (see below), whose sum is σ = 1789200. Its totient is φ = 306432.

The previous prime is 808993. The next prime is 809023. The reversal of 809020 is 20908.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809023) by changing a digit.

809020 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 685 + ... + 1444.

It is an arithmetic number, because the mean of its divisors is an integer number (74550).

2⁸⁰⁹⁰²⁰ is an apocalyptic number.

It is an amenable number.

809020 is an abundant number, since it is smaller than the sum of its proper divisors (980180).

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

809020 is a wasteful number, since it uses less digits than its factorization.

809020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2157 (or 2155 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 809020 is about 899.4553907782. The cubic root of 809020 is about 93.1793663299.

Adding to 809020 its reverse (20908), we get a palindrome (829928).

The spelling of 809020 in words is "eight hundred nine thousand, twenty".