8308681981 has 2 divisors, whose sum is σ = 8308681982. Its totient is φ = 8308681980.

The previous prime is 8308681963. The next prime is 8308681987. The reversal of 8308681981 is 1891868038.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8057934756 + 250747225 = 89766^2 + 15835^2 .

It is a cyclic number.

It is not a de Polignac number, because 8308681981 - 2²³ = 8300293373 is a prime.

It is a super-2 number, since 2×8308681981² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8308681987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4154340990 + 4154340991.

It is an arithmetic number, because the mean of its divisors is an integer number (4154340991).

Almost surely, 2^8308681981 is an apocalyptic number.

It is an amenable number.

8308681981 is a deficient number, since it is larger than the sum of its proper divisors (1).

8308681981 is an equidigital number, since it uses as much as digits as its factorization.

8308681981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 663552, while the sum is 52.

The square root of 8308681981 is about 91151.9718985826. The cubic root of 8308681981 is about 2025.3995639733.

The spelling of 8308681981 in words is "eight billion, three hundred eight million, six hundred eighty-one thousand, nine hundred eighty-one".