9999921939017 has 2 divisors, whose sum is σ = 9999921939018. Its totient is φ = 9999921939016.

The previous prime is 9999921938971. The next prime is 9999921939037. The reversal of 9999921939017 is 7109391299999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8104663103161 + 1895258835856 = 2846869^2 + 1376684^2 .

It is an emirp because it is prime and its reverse (7109391299999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9999921939017 - 2⁸ = 9999921938761 is a prime.

It is not a weakly prime, because it can be changed into another prime (9999921939037) 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, 4999960969508 + 4999960969509.

It is an arithmetic number, because the mean of its divisors is an integer number (4999960969509).

Almost surely, 2^{9999921939017} is an apocalyptic number.

It is an amenable number.

9999921939017 is a deficient number, since it is larger than the sum of its proper divisors (1).

9999921939017 is an equidigital number, since it uses as much as digits as its factorization.

9999921939017 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 200884698, while the sum is 77.

The spelling of 9999921939017 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred twenty-one million, nine hundred thirty-nine thousand, seventeen".