856631 has 8 divisors (see below), whose sum is σ = 897600. Its totient is φ = 816480.

The previous prime is 856627. The next prime is 856637. The reversal of 856631 is 136658.

856631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 856631 - 2² = 856627 is a prime.

It is a super-2 number, since 2×856631² = 1467633340322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 856594 and 856603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856637) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3026 + ... + 3296.

It is an arithmetic number, because the mean of its divisors is an integer number (112200).

2⁸⁵⁶⁶³¹ is an apocalyptic number.

856631 is a deficient number, since it is larger than the sum of its proper divisors (40969).

856631 is a wasteful number, since it uses less digits than its factorization.

856631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409.

The product of its digits is 4320, while the sum is 29.

The square root of 856631 is about 925.5436240394. The cubic root of 856631 is about 94.9725128233.

The spelling of 856631 in words is "eight hundred fifty-six thousand, six hundred thirty-one".