856539 has 12 divisors (see below), whose sum is σ = 1302600. Its totient is φ = 540864.

The previous prime is 856529. The next prime is 856547. The reversal of 856539 is 935658.

It is not a de Polignac number, because 856539 - 2⁵ = 856507 is a prime.

It is not an unprimeable number, because it can be changed into a prime (856519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2334 + ... + 2675.

It is an arithmetic number, because the mean of its divisors is an integer number (108550).

2⁸⁵⁶⁵³⁹ is an apocalyptic number.

856539 is a deficient number, since it is larger than the sum of its proper divisors (446061).

856539 is a wasteful number, since it uses less digits than its factorization.

856539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5034 (or 5031 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 856539 is about 925.4939221843. The cubic root of 856539 is about 94.9691127658.

The spelling of 856539 in words is "eight hundred fifty-six thousand, five hundred thirty-nine".