856636 has 12 divisors (see below), whose sum is σ = 1635480. Its totient is φ = 389360.

The previous prime is 856627. The next prime is 856637. The reversal of 856636 is 636658.

It is an Ulam number.

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 3 ways as a sum of consecutive naturals, for example, 9691 + ... + 9778.

It is an arithmetic number, because the mean of its divisors is an integer number (136290).

2⁸⁵⁶⁶³⁶ is an apocalyptic number.

It is an amenable number.

856636 is a deficient number, since it is larger than the sum of its proper divisors (778844).

856636 is a wasteful number, since it uses less digits than its factorization.

856636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19484 (or 19482 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 856636 is about 925.5463251507. The cubic root of 856636 is about 94.9726976020.

It can be divided in two parts, 8 and 56636, that added together give a square (56644 = 238²).

The spelling of 856636 in words is "eight hundred fifty-six thousand, six hundred thirty-six".