8665921 has 4 divisors (see below), whose sum is σ = 9453744. Its totient is φ = 7878100.

The previous prime is 8665913. The next prime is 8665931. The reversal of 8665921 is 1295668.

8665921 is digitally balanced in base 3, 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, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 8665921 - 2³ = 8665913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8665931) 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, 393895 + ... + 393916.

It is an arithmetic number, because the mean of its divisors is an integer number (2363436).

Almost surely, 2^8665921 is an apocalyptic number.

It is an amenable number.

8665921 is a deficient number, since it is larger than the sum of its proper divisors (787823).

8665921 is a wasteful number, since it uses less digits than its factorization.

8665921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787822.

The product of its digits is 25920, while the sum is 37.

The square root of 8665921 is about 2943.7936408655. The cubic root of 8665921 is about 205.4021137598.

The spelling of 8665921 in words is "eight million, six hundred sixty-five thousand, nine hundred twenty-one".