809885 has 4 divisors (see below), whose sum is σ = 971868. Its totient is φ = 647904.

The previous prime is 809869. The next prime is 809891. The reversal of 809885 is 588908.

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 343396 + 466489 = 586^2 + 683^2 .

It is a cyclic number.

It is not a de Polignac number, because 809885 - 2⁴ = 809869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 80984 + ... + 80993.

It is an arithmetic number, because the mean of its divisors is an integer number (242967).

2⁸⁰⁹⁸⁸⁵ is an apocalyptic number.

It is an amenable number.

809885 is a deficient number, since it is larger than the sum of its proper divisors (161983).

809885 is a wasteful number, since it uses less digits than its factorization.

809885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161982.

The product of its (nonzero) digits is 23040, while the sum is 38.

The square root of 809885 is about 899.9361088433. The cubic root of 809885 is about 93.2125634669.

The spelling of 809885 in words is "eight hundred nine thousand, eight hundred eighty-five".