856980859391 has 4 divisors (see below), whose sum is σ = 857003121984. Its totient is φ = 856958596800.

The previous prime is 856980859331. The next prime is 856980859409. The reversal of 856980859391 is 193958089658.

856980859391 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 a cyclic number.

It is not a de Polignac number, because 856980859391 - 2²² = 856976665087 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856980859331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11073455 + ... + 11150576.

It is an arithmetic number, because the mean of its divisors is an integer number (214250780496).

Almost surely, 2^856980859391 is an apocalyptic number.

856980859391 is a deficient number, since it is larger than the sum of its proper divisors (22262593).

856980859391 is a wasteful number, since it uses less digits than its factorization.

856980859391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22262592.

The product of its (nonzero) digits is 167961600, while the sum is 71.

The spelling of 856980859391 in words is "eight hundred fifty-six billion, nine hundred eighty million, eight hundred fifty-nine thousand, three hundred ninety-one".