856131 has 4 divisors (see below), whose sum is σ = 1141512. Its totient is φ = 570752.

The previous prime is 856117. The next prime is 856133. The reversal of 856131 is 131658.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 856131 - 2⁵ = 856099 is a prime.

It is a super-2 number, since 2×856131² = 1465920578322, which contains 22 as substring.

It is a D-number.

It is not an unprimeable number, because it can be changed into a prime (856133) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 142686 + ... + 142691.

It is an arithmetic number, because the mean of its divisors is an integer number (285378).

2⁸⁵⁶¹³¹ is an apocalyptic number.

856131 is a deficient number, since it is larger than the sum of its proper divisors (285381).

856131 is a wasteful number, since it uses less digits than its factorization.

856131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285380.

The product of its digits is 720, while the sum is 24.

The square root of 856131 is about 925.2734730878. The cubic root of 856131 is about 94.9540313152.

Adding to 856131 its reverse (131658), we get a palindrome (987789).

It can be divided in two parts, 85 and 6131, that added together give a triangular number (6216 = T₁₁₁).

The spelling of 856131 in words is "eight hundred fifty-six thousand, one hundred thirty-one".