809866885 has 8 divisors (see below), whose sum is σ = 972221976. Its totient is φ = 647639040.

The previous prime is 809866879. The next prime is 809866901. The reversal of 809866885 is 588668908.

It can be written as a sum of positive squares in 4 ways, for example, as 1147041 + 808719844 = 1071^2 + 28438^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 809866885 - 2⁵ = 809866853 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 7 ways as a sum of consecutive naturals, for example, 17196 + ... + 43765.

It is an arithmetic number, because the mean of its divisors is an integer number (121527747).

Almost surely, 2^809866885 is an apocalyptic number.

It is an amenable number.

809866885 is a deficient number, since it is larger than the sum of its proper divisors (162355091).

809866885 is a wasteful number, since it uses less digits than its factorization.

809866885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63623.

The product of its (nonzero) digits is 6635520, while the sum is 58.

The square root of 809866885 is about 28458.1602532560. The cubic root of 809866885 is about 932.1186848831.

The spelling of 809866885 in words is "eight hundred nine million, eight hundred sixty-six thousand, eight hundred eighty-five".