808921 has 8 divisors (see below), whose sum is σ = 837000. Its totient is φ = 781440.

The previous prime is 808919. The next prime is 808937. The reversal of 808921 is 129808.

It can be written as a sum of positive squares in 4 ways, for example, as 67600 + 741321 = 260^2 + 861^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 808921 - 2¹ = 808919 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 808921.

It is not an unprimeable number, because it can be changed into a prime (808961) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5355 + ... + 5503.

It is an arithmetic number, because the mean of its divisors is an integer number (104625).

2⁸⁰⁸⁹²¹ is an apocalyptic number.

It is an amenable number.

808921 is a deficient number, since it is larger than the sum of its proper divisors (28079).

808921 is a wasteful number, since it uses less digits than its factorization.

808921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 808921 is about 899.4003557927. The cubic root of 808921 is about 93.1755653800.

The spelling of 808921 in words is "eight hundred eight thousand, nine hundred twenty-one".