18781191936 has 216 divisors, whose sum is σ = 59421581856. Its totient is φ = 5669314560.

The previous prime is 18781191929. The next prime is 18781191967. The reversal of 18781191936 is 63919118781.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 1581541 + ... + 1593371.

It is an arithmetic number, because the mean of its divisors is an integer number (275099916).

Almost surely, 2^18781191936 is an apocalyptic number.

18781191936 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18781191936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29710790928).

18781191936 is an abundant number, since it is smaller than the sum of its proper divisors (40640389920).

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

18781191936 is a wasteful number, since it uses less digits than its factorization.

18781191936 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11919 (or 11902 counting only the distinct ones).

The product of its digits is 653184, while the sum is 54.

The spelling of 18781191936 in words is "eighteen billion, seven hundred eighty-one million, one hundred ninety-one thousand, nine hundred thirty-six".