856675921 has 16 divisors (see below), whose sum is σ = 902880000. Its totient is φ = 811714176.

The previous prime is 856675913. The next prime is 856675931. The reversal of 856675921 is 129576658.

It is not a de Polignac number, because 856675921 - 2³ = 856675913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (856675901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 409045 + ... + 411133.

It is an arithmetic number, because the mean of its divisors is an integer number (56430000).

Almost surely, 2^856675921 is an apocalyptic number.

It is an amenable number.

856675921 is a deficient number, since it is larger than the sum of its proper divisors (46204079).

856675921 is a wasteful number, since it uses less digits than its factorization.

856675921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2376.

The product of its digits is 907200, while the sum is 49.

The square root of 856675921 is about 29269.0266493438. The cubic root of 856675921 is about 949.7417288683.

The spelling of 856675921 in words is "eight hundred fifty-six million, six hundred seventy-five thousand, nine hundred twenty-one".