856836 has 18 divisors (see below), whose sum is σ = 2165982. Its totient is φ = 285600.

The previous prime is 856831. The next prime is 856841. The reversal of 856836 is 638658.

It is an interprime number because it is at equal distance from previous prime (856831) and next prime (856841).

It can be written as a sum of positive squares in only one way, i.e., 799236 + 57600 = 894^2 + 240^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 23801 = 856836 / (8 + 5 + 6 + 8 + 3 + 6).

It is a self number, because there is not a number n which added to its sum of digits gives 856836.

It is not an unprimeable number, because it can be changed into a prime (856831) by changing a digit.

856836 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11865 + ... + 11936.

2⁸⁵⁶⁸³⁶ is an apocalyptic number.

It is an amenable number.

856836 is an abundant number, since it is smaller than the sum of its proper divisors (1309146).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

856836 is a wasteful number, since it uses less digits than its factorization.

856836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23811 (or 23806 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 856836 is about 925.6543631399. The cubic root of 856836 is about 94.9800881629.

The spelling of 856836 in words is "eight hundred fifty-six thousand, eight hundred thirty-six".