18818288640 has 264 divisors, whose sum is σ = 66599881920. Its totient is φ = 4910874624.

The previous prime is 18818288623. The next prime is 18818288651. The reversal of 18818288640 is 4688281881.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2161416 + ... + 2170104.

It is an arithmetic number, because the mean of its divisors is an integer number (252272280).

Almost surely, 2^18818288640 is an apocalyptic number.

18818288640 is a gapful number since it is divisible by the number (10) 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 18818288640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33299940960).

18818288640 is an abundant number, since it is smaller than the sum of its proper divisors (47781593280).

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

18818288640 is a wasteful number, since it uses less digits than its factorization.

18818288640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8767 (or 8746 counting only the distinct ones).

The product of its (nonzero) digits is 1572864, while the sum is 54.

The spelling of 18818288640 in words is "eighteen billion, eight hundred eighteen million, two hundred eighty-eight thousand, six hundred forty".