18564436717 has 2 divisors, whose sum is σ = 18564436718. Its totient is φ = 18564436716.

The previous prime is 18564436711. The next prime is 18564436777. The reversal of 18564436717 is 71763446581.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16738925641 + 1825511076 = 129379^2 + 42726^2 .

It is a cyclic number.

It is not a de Polignac number, because 18564436717 - 2⁷ = 18564436589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18564436711) 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, 9282218358 + 9282218359.

It is an arithmetic number, because the mean of its divisors is an integer number (9282218359).

Almost surely, 2^18564436717 is an apocalyptic number.

It is an amenable number.

18564436717 is a deficient number, since it is larger than the sum of its proper divisors (1).

18564436717 is an equidigital number, since it uses as much as digits as its factorization.

18564436717 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3386880, while the sum is 52.

The spelling of 18564436717 in words is "eighteen billion, five hundred sixty-four million, four hundred thirty-six thousand, seven hundred seventeen".