856519664 has 80 divisors (see below), whose sum is σ = 2228190720. Its totient is φ = 308033280.

The previous prime is 856519663. The next prime is 856519717. The reversal of 856519664 is 466915658.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856519661) 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, 10724 + ... + 42755.

It is an arithmetic number, because the mean of its divisors is an integer number (27852384).

Almost surely, 2^856519664 is an apocalyptic number.

It is an amenable number.

856519664 is an abundant number, since it is smaller than the sum of its proper divisors (1371671056).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

856519664 is a wasteful number, since it uses less digits than its factorization.

856519664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53518 (or 53512 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 50.

The square root of 856519664 is about 29266.3572041346. The cubic root of 856519664 is about 949.6839813142.

The spelling of 856519664 in words is "eight hundred fifty-six million, five hundred nineteen thousand, six hundred sixty-four".