18686217888 has 768 divisors, whose sum is σ = 66653798400. Its totient is φ = 5099314176.

The previous prime is 18686217859. The next prime is 18686217899. The reversal of 18686217888 is 88871268681.

It is a super-2 number, since 2×18686217888² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 397579081 + ... + 397579127.

It is an arithmetic number, because the mean of its divisors is an integer number (86788800).

Almost surely, 2^18686217888 is an apocalyptic number.

18686217888 is a gapful number since it is divisible by the number (18) 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 18686217888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33326899200).

18686217888 is an abundant number, since it is smaller than the sum of its proper divisors (47967580512).

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

18686217888 is a wasteful number, since it uses less digits than its factorization.

18686217888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133 (or 107 counting only the distinct ones).

The product of its digits is 16515072, while the sum is 63.

The spelling of 18686217888 in words is "eighteen billion, six hundred eighty-six million, two hundred seventeen thousand, eight hundred eighty-eight".