856806531 has 16 divisors (see below), whose sum is σ = 1306450944. Its totient is φ = 489288384.

The previous prime is 856806499. The next prime is 856806541. The reversal of 856806531 is 135608658.

It is not a de Polignac number, because 856806531 - 2⁵ = 856806499 is a prime.

It is a super-2 number, since 2×856806531² = 1468234863128507922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (856806541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22486 + ... + 47108.

It is an arithmetic number, because the mean of its divisors is an integer number (81653184).

Almost surely, 2^856806531 is an apocalyptic number.

856806531 is a deficient number, since it is larger than the sum of its proper divisors (449644413).

856806531 is a wasteful number, since it uses less digits than its factorization.

856806531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26290.

The product of its (nonzero) digits is 172800, while the sum is 42.

The square root of 856806531 is about 29271.2577625219. The cubic root of 856806531 is about 949.7899927297.

The spelling of 856806531 in words is "eight hundred fifty-six million, eight hundred six thousand, five hundred thirty-one".