6856 has 8 divisors (see below), whose sum is σ = 12870. Its totient is φ = 3424.

The previous prime is 6841. The next prime is 6857. The reversal of 6856 is 6586.

It can be written as a sum of positive squares in only one way, i.e., 4356 + 2500 = 66^2 + 50^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a self number, because there is not a number n which added to its sum of digits gives 6856.

It is not an unprimeable number, because it can be changed into a prime (6857) by changing a digit.

6856 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 421 + ... + 436.

2⁶⁸⁵⁶ is an apocalyptic number.

It is an amenable number.

6856 is a deficient number, since it is larger than the sum of its proper divisors (6014).

6856 is a wasteful number, since it uses less digits than its factorization.

6856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 863 (or 859 counting only the distinct ones).

The product of its digits is 1440, while the sum is 25.

The square root of 6856 is about 82.8009661779. The cubic root of 6856 is about 18.9972295129.

The spelling of 6856 in words is "six thousand, eight hundred fifty-six".