18381636819 has 48 divisors (see below), whose sum is σ = 32765241600. Its totient is φ = 9670062528.

The previous prime is 18381636799. The next prime is 18381636821. The reversal of 18381636819 is 91863618381.

It is not a de Polignac number, because 18381636819 - 2¹¹ = 18381634771 is a prime.

It is a super-2 number, since 2×18381636819² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18381636839) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 280792 + ... + 340010.

It is an arithmetic number, because the mean of its divisors is an integer number (682609200).

Almost surely, 2^18381636819 is an apocalyptic number.

18381636819 is a deficient number, since it is larger than the sum of its proper divisors (14383604781).

18381636819 is a wasteful number, since it uses less digits than its factorization.

18381636819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59624 (or 59621 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 54.

The spelling of 18381636819 in words is "eighteen billion, three hundred eighty-one million, six hundred thirty-six thousand, eight hundred nineteen".