804809 has 4 divisors (see below), whose sum is σ = 813204. Its totient is φ = 796416.

The previous prime is 804803. The next prime is 804823. The reversal of 804809 is 908408.

804809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 644809 + 160000 = 803^2 + 400^2 .

It is a cyclic number.

It is not a de Polignac number, because 804809 - 2⁸ = 804553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (804803) 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, 4052 + ... + 4245.

It is an arithmetic number, because the mean of its divisors is an integer number (203301).

2⁸⁰⁴⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

804809 is a deficient number, since it is larger than the sum of its proper divisors (8395).

804809 is an equidigital number, since it uses as much as digits as its factorization.

804809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8394.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 804809 is about 897.1114757933. Note that the first 3 decimals coincide. The cubic root of 804809 is about 93.0174168636.

The spelling of 804809 in words is "eight hundred four thousand, eight hundred nine".