18981467987 has 8 divisors (see below), whose sum is σ = 19399432512. Its totient is φ = 18564091200.

The previous prime is 18981467983. The next prime is 18981467993. The reversal of 18981467987 is 78976418981.

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 18981467987 - 2² = 18981467983 is a prime.

It is a super-2 number, since 2×18981467987² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18981467983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 81314 + ... + 211127.

It is an arithmetic number, because the mean of its divisors is an integer number (2424929064).

Almost surely, 2^18981467987 is an apocalyptic number.

18981467987 is a deficient number, since it is larger than the sum of its proper divisors (417964525).

18981467987 is a wasteful number, since it uses less digits than its factorization.

18981467987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 293869.

The product of its digits is 48771072, while the sum is 68.

The spelling of 18981467987 in words is "eighteen billion, nine hundred eighty-one million, four hundred sixty-seven thousand, nine hundred eighty-seven".