18318266650889 has 2 divisors, whose sum is σ = 18318266650890. Its totient is φ = 18318266650888.

The previous prime is 18318266650777. The next prime is 18318266650897. The reversal of 18318266650889 is 98805666281381.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9335010855625 + 8983255795264 = 3055325^2 + 2997208^2 .

It is an emirp because it is prime and its reverse (98805666281381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18318266650889 - 2²⁴ = 18318249873673 is a prime.

It is not a weakly prime, because it can be changed into another prime (18318266620889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9159133325444 + 9159133325445.

It is an arithmetic number, because the mean of its divisors is an integer number (9159133325445).

Almost surely, 2^{18318266650889} is an apocalyptic number.

It is an amenable number.

18318266650889 is a deficient number, since it is larger than the sum of its proper divisors (1).

18318266650889 is an equidigital number, since it uses as much as digits as its factorization.

18318266650889 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 238878720, while the sum is 71.

The spelling of 18318266650889 in words is "eighteen trillion, three hundred eighteen billion, two hundred sixty-six million, six hundred fifty thousand, eight hundred eighty-nine".