6668008981 has 2 divisors, whose sum is σ = 6668008982. Its totient is φ = 6668008980.

The previous prime is 6668008973. The next prime is 6668008999. The reversal of 6668008981 is 1898008666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6523792900 + 144216081 = 80770^2 + 12009^2 .

It is a cyclic number.

It is not a de Polignac number, because 6668008981 - 2³ = 6668008973 is a prime.

It is a super-2 number, since 2×6668008981² = 88924687541393316722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6668000981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3334004490 + 3334004491.

It is an arithmetic number, because the mean of its divisors is an integer number (3334004491).

Almost surely, 2^6668008981 is an apocalyptic number.

It is an amenable number.

6668008981 is a deficient number, since it is larger than the sum of its proper divisors (1).

6668008981 is an equidigital number, since it uses as much as digits as its factorization.

6668008981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 995328, while the sum is 52.

The square root of 6668008981 is about 81657.8776420255. The cubic root of 6668008981 is about 1882.1983659002.

The spelling of 6668008981 in words is "six billion, six hundred sixty-eight million, eight thousand, nine hundred eighty-one".