18947385604117 has 2 divisors, whose sum is σ = 18947385604118. Its totient is φ = 18947385604116.

The previous prime is 18947385604057. The next prime is 18947385604127. The reversal of 18947385604117 is 71140658374981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12575527347601 + 6371858256516 = 3546199^2 + 2524254^2 .

It is a cyclic number.

It is not a de Polignac number, because 18947385604117 - 2⁷ = 18947385603989 is a prime.

It is a super-2 number, since 2×18947385604117² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18947385604127) 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, 9473692802058 + 9473692802059.

It is an arithmetic number, because the mean of its divisors is an integer number (9473692802059).

Almost surely, 2^{18947385604117} is an apocalyptic number.

It is an amenable number.

18947385604117 is a deficient number, since it is larger than the sum of its proper divisors (1).

18947385604117 is an equidigital number, since it uses as much as digits as its factorization.

18947385604117 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40642560, while the sum is 64.

The spelling of 18947385604117 in words is "eighteen trillion, nine hundred forty-seven billion, three hundred eighty-five million, six hundred four thousand, one hundred seventeen".