856380664885 has 4 divisors (see below), whose sum is σ = 1027656797868. Its totient is φ = 685104531904.

The previous prime is 856380664879. The next prime is 856380664891. The reversal of 856380664885 is 588466083658.

856380664885 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (856380664879) and next prime (856380664891).

It can be written as a sum of positive squares in 2 ways, for example, as 195592138564 + 660788526321 = 442258^2 + 812889^2 .

It is a cyclic number.

It is not a de Polignac number, because 856380664885 - 2¹³ = 856380656693 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 856380664885.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85638066484 + ... + 85638066493.

It is an arithmetic number, because the mean of its divisors is an integer number (256914199467).

Almost surely, 2^856380664885 is an apocalyptic number.

It is an amenable number.

856380664885 is a deficient number, since it is larger than the sum of its proper divisors (171276132983).

856380664885 is a wasteful number, since it uses less digits than its factorization.

856380664885 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171276132982.

The product of its (nonzero) digits is 265420800, while the sum is 67.

The spelling of 856380664885 in words is "eight hundred fifty-six billion, three hundred eighty million, six hundred sixty-four thousand, eight hundred eighty-five".