6856647 has 16 divisors (see below), whose sum is σ = 10583040. Its totient is φ = 3867552.

The previous prime is 6856643. The next prime is 6856669. The reversal of 6856647 is 7466586.

It is a happy number.

6856647 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6856647 - 2² = 6856643 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 6856599 and 6856608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6856643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 408 + ... + 3725.

It is an arithmetic number, because the mean of its divisors is an integer number (661440).

Almost surely, 2^6856647 is an apocalyptic number.

6856647 is a deficient number, since it is larger than the sum of its proper divisors (3726393).

6856647 is a wasteful number, since it uses less digits than its factorization.

6856647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4222.

The product of its digits is 241920, while the sum is 42.

The square root of 6856647 is about 2618.5200018331. The cubic root of 6856647 is about 189.9782708299.

It can be divided in two parts, 6856 and 647, that added together give a triangular number (7503 = T₁₂₂).

The spelling of 6856647 in words is "six million, eight hundred fifty-six thousand, six hundred forty-seven".