18993064693 has 2 divisors, whose sum is σ = 18993064694. Its totient is φ = 18993064692.

The previous prime is 18993064681. The next prime is 18993064703. The reversal of 18993064693 is 39646039981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11676315249 + 7316749444 = 108057^2 + 85538^2 .

It is an emirp because it is prime and its reverse (39646039981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18993064693 - 2¹³ = 18993056501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18993068693) 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, 9496532346 + 9496532347.

It is an arithmetic number, because the mean of its divisors is an integer number (9496532347).

Almost surely, 2^18993064693 is an apocalyptic number.

It is an amenable number.

18993064693 is a deficient number, since it is larger than the sum of its proper divisors (1).

18993064693 is an equidigital number, since it uses as much as digits as its factorization.

18993064693 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7558272, while the sum is 58.

The spelling of 18993064693 in words is "eighteen billion, nine hundred ninety-three million, sixty-four thousand, six hundred ninety-three".