16668931 has 2 divisors, whose sum is σ = 16668932. Its totient is φ = 16668930.

The previous prime is 16668929. The next prime is 16668937. The reversal of 16668931 is 13986661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16668931 - 2¹ = 16668929 is a prime.

It is a super-2 number, since 2×16668931² = 555706521365522, which contains 22 as substring.

Together with 16668929, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16668937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8334465 + 8334466.

It is an arithmetic number, because the mean of its divisors is an integer number (8334466).

Almost surely, 2^16668931 is an apocalyptic number.

16668931 is a deficient number, since it is larger than the sum of its proper divisors (1).

16668931 is an equidigital number, since it uses as much as digits as its factorization.

16668931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 40.

The square root of 16668931 is about 4082.7602182837. The cubic root of 16668931 is about 255.4480448073.

The spelling of 16668931 in words is "sixteen million, six hundred sixty-eight thousand, nine hundred thirty-one".