856584355021 has 8 divisors (see below), whose sum is σ = 874822515840. Its totient is φ = 838346734368.

The previous prime is 856584355009. The next prime is 856584355043. The reversal of 856584355021 is 120553485658.

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 856584355021 - 2¹¹ = 856584352973 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 856584355021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856584355001) 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, 6175785 + ... + 6312961.

It is an arithmetic number, because the mean of its divisors is an integer number (109352814480).

Almost surely, 2^856584355021 is an apocalyptic number.

It is an amenable number.

856584355021 is a deficient number, since it is larger than the sum of its proper divisors (18238160819).

856584355021 is a wasteful number, since it uses less digits than its factorization.

856584355021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270083.

The product of its (nonzero) digits is 5760000, while the sum is 52.

The spelling of 856584355021 in words is "eight hundred fifty-six billion, five hundred eighty-four million, three hundred fifty-five thousand, twenty-one".