856044440658 has 128 divisors (see below), whose sum is σ = 2132472545280. Its totient is φ = 252263160000.

The previous prime is 856044440623. The next prime is 856044440717.

856044440658 is a `hidden beast` number, since 85 + 60 + 4 + 4 + 440 + 65 + 8 = 666.

856044440658 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 46386333 + ... + 46404783.

It is an arithmetic number, because the mean of its divisors is an integer number (16659941760).

Almost surely, 2^856044440658 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 856044440658, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1066236272640).

856044440658 is an abundant number, since it is smaller than the sum of its proper divisors (1276428104622).

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

856044440658 is a wasteful number, since it uses less digits than its factorization.

856044440658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20621 (or 20615 counting only the distinct ones).

The product of its (nonzero) digits is 14745600, while the sum is 54.

The spelling of 856044440658 in words is "eight hundred fifty-six billion, forty-four million, four hundred forty thousand, six hundred fifty-eight".