856637 has 2 divisors, whose sum is σ = 856638. Its totient is φ = 856636.

The previous prime is 856627. The next prime is 856649. The reversal of 856637 is 736658.

It is a happy number.

856637 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 657721 + 198916 = 811^2 + 446^2 .

It is a cyclic number.

It is not a de Polignac number, because 856637 - 2⁸ = 856381 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 856597 and 856606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (856627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428318 + 428319.

It is an arithmetic number, because the mean of its divisors is an integer number (428319).

2⁸⁵⁶⁶³⁷ is an apocalyptic number.

It is an amenable number.

856637 is a deficient number, since it is larger than the sum of its proper divisors (1).

856637 is an equidigital number, since it uses as much as digits as its factorization.

856637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 35.

The square root of 856637 is about 925.5468653720. The cubic root of 856637 is about 94.9727345577.

The spelling of 856637 in words is "eight hundred fifty-six thousand, six hundred thirty-seven".