18981618864497 has 8 divisors (see below), whose sum is σ = 19003207606272. Its totient is φ = 18960034542400.

The previous prime is 18981618864493. The next prime is 18981618864499. The reversal of 18981618864497 is 79446881618981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18981618864497 - 2² = 18981618864493 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18981618864493) 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 in 7 ways as a sum of consecutive naturals, for example, 7527872 + ... + 9727902.

It is an arithmetic number, because the mean of its divisors is an integer number (2375400950784).

Almost surely, 2^{18981618864497} is an apocalyptic number.

It is an amenable number.

18981618864497 is a deficient number, since it is larger than the sum of its proper divisors (21588741775).

18981618864497 is an equidigital number, since it uses as much as digits as its factorization.

18981618864497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2209839.

The product of its digits is 1337720832, while the sum is 80.

The spelling of 18981618864497 in words is "eighteen trillion, nine hundred eighty-one billion, six hundred eighteen million, eight hundred sixty-four thousand, four hundred ninety-seven".