6688981 has 8 divisors (see below), whose sum is σ = 7305984. Its totient is φ = 6086640.

The previous prime is 6688967. The next prime is 6688999. The reversal of 6688981 is 1898866.

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 6688981 - 2⁷ = 6688853 is a prime.

It is a super-2 number, since 2×6688981² = 89484933636722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6688481) 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, 2701 + ... + 4546.

It is an arithmetic number, because the mean of its divisors is an integer number (913248).

Almost surely, 2^6688981 is an apocalyptic number.

It is an amenable number.

6688981 is a deficient number, since it is larger than the sum of its proper divisors (617003).

6688981 is a wasteful number, since it uses less digits than its factorization.

6688981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7331.

The product of its digits is 165888, while the sum is 46.

The square root of 6688981 is about 2586.3064396935. The cubic root of 6688981 is about 188.4169578424.

The spelling of 6688981 in words is "six million, six hundred eighty-eight thousand, nine hundred eighty-one".