6816881 has 8 divisors (see below), whose sum is σ = 7253064. Its totient is φ = 6384640.

The previous prime is 6816871. The next prime is 6816889. The reversal of 6816881 is 1886186.

It can be written as a sum of positive squares in 4 ways, for example, as 1600225 + 5216656 = 1265^2 + 2284^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6816881 - 2²² = 2622577 is a prime.

It is a super-2 number, since 2×6816881² = 92939733136322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6816889) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3101 + ... + 4821.

It is an arithmetic number, because the mean of its divisors is an integer number (906633).

Almost surely, 2^6816881 is an apocalyptic number.

It is an amenable number.

6816881 is a deficient number, since it is larger than the sum of its proper divisors (436183).

6816881 is a wasteful number, since it uses less digits than its factorization.

6816881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1971.

The product of its digits is 18432, while the sum is 38.

The square root of 6816881 is about 2610.9157397358. The cubic root of 6816881 is about 189.6102907795.

The spelling of 6816881 in words is "six million, eight hundred sixteen thousand, eight hundred eighty-one".