8081999689 has 2 divisors, whose sum is σ = 8081999690. Its totient is φ = 8081999688.

The previous prime is 8081999659. The next prime is 8081999719. The reversal of 8081999689 is 9869991808.

It is a balanced prime because it is at equal distance from previous prime (8081999659) and next prime (8081999719).

It can be written as a sum of positive squares in only one way, i.e., 8080571664 + 1428025 = 89892^2 + 1195^2 .

It is a cyclic number.

It is not a de Polignac number, because 8081999689 - 2²⁵ = 8048445257 is a prime.

It is not a weakly prime, because it can be changed into another prime (8081999659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4040999844 + 4040999845.

It is an arithmetic number, because the mean of its divisors is an integer number (4040999845).

Almost surely, 2^8081999689 is an apocalyptic number.

It is an amenable number.

8081999689 is a deficient number, since it is larger than the sum of its proper divisors (1).

8081999689 is an equidigital number, since it uses as much as digits as its factorization.

8081999689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20155392, while the sum is 67.

The square root of 8081999689 is about 89899.9426529294. The cubic root of 8081999689 is about 2006.8100924178.

The spelling of 8081999689 in words is "eight billion, eighty-one million, nine hundred ninety-nine thousand, six hundred eighty-nine".