6681931 has 2 divisors, whose sum is σ = 6681932. Its totient is φ = 6681930.

The previous prime is 6681929. The next prime is 6681947. The reversal of 6681931 is 1391866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6681931 - 2¹ = 6681929 is a prime.

It is a super-2 number, since 2×6681931² = 89296403777522, which contains 22 as substring.

Together with 6681929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (6681971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3340965 + 3340966.

It is an arithmetic number, because the mean of its divisors is an integer number (3340966).

Almost surely, 2^6681931 is an apocalyptic number.

6681931 is a deficient number, since it is larger than the sum of its proper divisors (1).

6681931 is an equidigital number, since it uses as much as digits as its factorization.

6681931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 34.

The square root of 6681931 is about 2584.9431328368. The cubic root of 6681931 is about 188.3507391610.

The spelling of 6681931 in words is "six million, six hundred eighty-one thousand, nine hundred thirty-one".