18939770784 has 192 divisors, whose sum is σ = 60447098880. Its totient is φ = 5721788160.

The previous prime is 18939770777. The next prime is 18939770797. The reversal of 18939770784 is 48707793981.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3295017 + ... + 3300759.

It is an arithmetic number, because the mean of its divisors is an integer number (314828640).

Almost surely, 2^18939770784 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18939770784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30223549440).

18939770784 is an abundant number, since it is smaller than the sum of its proper divisors (41507328096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18939770784 is a wasteful number, since it uses less digits than its factorization.

18939770784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6120 (or 6106 counting only the distinct ones).

The product of its (nonzero) digits is 21337344, while the sum is 63.

The spelling of 18939770784 in words is "eighteen billion, nine hundred thirty-nine million, seven hundred seventy thousand, seven hundred eighty-four".