856861344 has 72 divisors (see below), whose sum is σ = 2493402912. Its totient is φ = 278974080.

The previous prime is 856861339. The next prime is 856861351. The reversal of 856861344 is 443168658.

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×856861344² = 1468422725682972672, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 856861344.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22212 + ... + 46979.

It is an arithmetic number, because the mean of its divisors is an integer number (34630596).

Almost surely, 2^856861344 is an apocalyptic number.

It is an amenable number.

856861344 is an abundant number, since it is smaller than the sum of its proper divisors (1636541568).

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

856861344 is a wasteful number, since it uses less digits than its factorization.

856861344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69250 (or 69239 counting only the distinct ones).

The product of its digits is 552960, while the sum is 45.

The square root of 856861344 is about 29272.1940414449. The cubic root of 856861344 is about 949.8102461268.

The spelling of 856861344 in words is "eight hundred fifty-six million, eight hundred sixty-one thousand, three hundred forty-four".