17991616693 has 2 divisors, whose sum is σ = 17991616694. Its totient is φ = 17991616692.

The previous prime is 17991616673. The next prime is 17991616703. The reversal of 17991616693 is 39661619971.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12512212164 + 5479404529 = 111858^2 + 74023^2 .

It is an emirp because it is prime and its reverse (39661619971) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17991616693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17991616603) 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, 8995808346 + 8995808347.

It is an arithmetic number, because the mean of its divisors is an integer number (8995808347).

Almost surely, 2^17991616693 is an apocalyptic number.

It is an amenable number.

17991616693 is a deficient number, since it is larger than the sum of its proper divisors (1).

17991616693 is an equidigital number, since it uses as much as digits as its factorization.

17991616693 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3306744, while the sum is 58.

The spelling of 17991616693 in words is "seventeen billion, nine hundred ninety-one million, six hundred sixteen thousand, six hundred ninety-three".