18993242416 has 20 divisors (see below), whose sum is σ = 37655208712. Its totient is φ = 9275769216.

The previous prime is 18993242413. The next prime is 18993242423. The reversal of 18993242416 is 61424239981.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18993242416.

It is not an unprimeable number, because it can be changed into a prime (18993242413) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13802541 + ... + 13803916.

Almost surely, 2^18993242416 is an apocalyptic number.

18993242416 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18993242416 is a deficient number, since it is larger than the sum of its proper divisors (18661966296).

18993242416 is a wasteful number, since it uses less digits than its factorization.

18993242416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27606508 (or 27606502 counting only the distinct ones).

The product of its digits is 746496, while the sum is 49.

The spelling of 18993242416 in words is "eighteen billion, nine hundred ninety-three million, two hundred forty-two thousand, four hundred sixteen".