805809 has 16 divisors (see below), whose sum is σ = 1153280. Its totient is φ = 498960.

The previous prime is 805807. The next prime is 805811. The reversal of 805809 is 908508.

805809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (805807) and next prime (805811).

It is not a de Polignac number, because 805809 - 2¹ = 805807 is a prime.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 805809.

It is not an unprimeable number, because it can be changed into a prime (805807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3714 + ... + 3924.

It is an arithmetic number, because the mean of its divisors is an integer number (72080).

2⁸⁰⁵⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

805809 is a deficient number, since it is larger than the sum of its proper divisors (347471).

805809 is a wasteful number, since it uses less digits than its factorization.

805809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300.

The product of its (nonzero) digits is 2880, while the sum is 30.

The square root of 805809 is about 897.6686471076. The cubic root of 805809 is about 93.0559265878.

The spelling of 805809 in words is "eight hundred five thousand, eight hundred nine".