856975631 has 4 divisors (see below), whose sum is σ = 860653872. Its totient is φ = 853297392.

The previous prime is 856975619. The next prime is 856975633. The reversal of 856975631 is 136579658.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856975631 is a prime.

It is a super-2 number, since 2×856975631² = 1468814464255696322, which contains 22 as substring.

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 856975631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856975633) 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, 1838771 + ... + 1839236.

It is an arithmetic number, because the mean of its divisors is an integer number (215163468).

Almost surely, 2^856975631 is an apocalyptic number.

856975631 is a deficient number, since it is larger than the sum of its proper divisors (3678241).

856975631 is a wasteful number, since it uses less digits than its factorization.

856975631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3678240.

The product of its digits is 1360800, while the sum is 50.

The square root of 856975631 is about 29274.1461190587. The cubic root of 856975631 is about 949.8524723822.

The spelling of 856975631 in words is "eight hundred fifty-six million, nine hundred seventy-five thousand, six hundred thirty-one".