18981618814589 has 2 divisors, whose sum is σ = 18981618814590. Its totient is φ = 18981618814588.

The previous prime is 18981618814531. The next prime is 18981618814679. The reversal of 18981618814589 is 98541881618981.

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., 18707718358564 + 273900456025 = 4325242^2 + 523355^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18981618814589 is a prime.

It is a super-3 number, since 3×18981618814589³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18981618814189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9490809407294 + 9490809407295.

It is an arithmetic number, because the mean of its divisors is an integer number (9490809407295).

Almost surely, 2^{18981618814589} is an apocalyptic number.

It is an amenable number.

18981618814589 is a deficient number, since it is larger than the sum of its proper divisors (1).

18981618814589 is an equidigital number, since it uses as much as digits as its factorization.

18981618814589 is an evil number, because the sum of its binary digits is even.

The product of its digits is 318504960, while the sum is 77.

The spelling of 18981618814589 in words is "eighteen trillion, nine hundred eighty-one billion, six hundred eighteen million, eight hundred fourteen thousand, five hundred eighty-nine".