809873 has 4 divisors (see below), whose sum is σ = 829668. Its totient is φ = 790080.

The previous prime is 809869. The next prime is 809891. The reversal of 809873 is 378908.

809873 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 117649 + 692224 = 343^2 + 832^2 .

It is a cyclic number.

It is not a de Polignac number, because 809873 - 2² = 809869 is a prime.

It is a super-2 number, since 2×809873² = 1311788552258, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (809803) 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, 9836 + ... + 9917.

It is an arithmetic number, because the mean of its divisors is an integer number (207417).

2⁸⁰⁹⁸⁷³ is an apocalyptic number.

It is an amenable number.

809873 is a deficient number, since it is larger than the sum of its proper divisors (19795).

809873 is a wasteful number, since it uses less digits than its factorization.

809873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19794.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 809873 is about 899.9294416786. The cubic root of 809873 is about 93.2121030903.

Adding to 809873 its sum of digits (35), we get a palindrome (809908).

The spelling of 809873 in words is "eight hundred nine thousand, eight hundred seventy-three".