6856531 has 4 divisors (see below), whose sum is σ = 7479864. Its totient is φ = 6233200.

The previous prime is 6856529. The next prime is 6856537. The reversal of 6856531 is 1356586.

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 6856531 - 2¹ = 6856529 is a prime.

It is a super-2 number, since 2×6856531² = 94024034707922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6856537) 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 3 ways as a sum of consecutive naturals, for example, 311650 + ... + 311671.

It is an arithmetic number, because the mean of its divisors is an integer number (1869966).

Almost surely, 2^6856531 is an apocalyptic number.

6856531 is a deficient number, since it is larger than the sum of its proper divisors (623333).

6856531 is a wasteful number, since it uses less digits than its factorization.

6856531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 623332.

The product of its digits is 21600, while the sum is 34.

The square root of 6856531 is about 2618.4978518227. The cubic root of 6856531 is about 189.9771994801.

Subtracting from 6856531 its reverse (1356586), we obtain a palindrome (5499945).

The spelling of 6856531 in words is "six million, eight hundred fifty-six thousand, five hundred thirty-one".