18988809380 has 72 divisors (see below), whose sum is σ = 42200154360. Its totient is φ = 7176199680.

The previous prime is 18988809353. The next prime is 18988809397. The reversal of 18988809380 is 8390888981.

It can be written as a sum of positive squares in 4 ways, for example, as 2138692516 + 16850116864 = 46246^2 + 129808^2 .

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, 2805200 + ... + 2811960.

It is an arithmetic number, because the mean of its divisors is an integer number (586113255).

Almost surely, 2^18988809380 is an apocalyptic number.

18988809380 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 18988809380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21100077180).

18988809380 is an abundant number, since it is smaller than the sum of its proper divisors (23211344980).

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

18988809380 is a wasteful number, since it uses less digits than its factorization.

18988809380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7197 (or 7176 counting only the distinct ones).

The product of its (nonzero) digits is 7962624, while the sum is 62.

The spelling of 18988809380 in words is "eighteen billion, nine hundred eighty-eight million, eight hundred nine thousand, three hundred eighty".