856531564 has 36 divisors (see below), whose sum is σ = 1745513280. Its totient is φ = 366693600.

The previous prime is 856531549. The next prime is 856531567. The reversal of 856531564 is 465135658.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 856531564.

It is not an unprimeable number, because it can be changed into a prime (856531567) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 253317 + ... + 256675.

It is an arithmetic number, because the mean of its divisors is an integer number (48486480).

Almost surely, 2^856531564 is an apocalyptic number.

It is an amenable number.

856531564 is an abundant number, since it is smaller than the sum of its proper divisors (888981716).

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

856531564 is a wasteful number, since it uses less digits than its factorization.

856531564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4678 (or 4669 counting only the distinct ones).

The product of its digits is 432000, while the sum is 43.

The square root of 856531564 is about 29266.5605085394. The cubic root of 856531564 is about 949.6883794180.

The spelling of 856531564 in words is "eight hundred fifty-six million, five hundred thirty-one thousand, five hundred sixty-four".