856864 has 12 divisors (see below), whose sum is σ = 1687014. Its totient is φ = 428416.

The previous prime is 856853. The next prime is 856897. The reversal of 856864 is 468658.

856864 is nontrivially palindromic in base 7.

It can be written as a sum of positive squares in only one way, i.e., 824464 + 32400 = 908^2 + 180^2 .

It is a zygodrome in base 15.

It is an unprimeable 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 as a sum of consecutive naturals, namely, 13357 + ... + 13420.

2⁸⁵⁶⁸⁶⁴ is an apocalyptic number.

It is an amenable number.

856864 is a deficient number, since it is larger than the sum of its proper divisors (830150).

856864 is a wasteful number, since it uses less digits than its factorization.

856864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26787 (or 26779 counting only the distinct ones).

The product of its digits is 46080, while the sum is 37.

The square root of 856864 is about 925.6694874522. The cubic root of 856864 is about 94.9811227497.

The spelling of 856864 in words is "eight hundred fifty-six thousand, eight hundred sixty-four".