18889547440 has 80 divisors (see below), whose sum is σ = 45392808960. Its totient is φ = 7302746880.

The previous prime is 18889547437. The next prime is 18889547449. The reversal of 18889547440 is 4474598881.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (18889547449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2125887 + ... + 2134753.

It is an arithmetic number, because the mean of its divisors is an integer number (567410112).

Almost surely, 2^18889547440 is an apocalyptic number.

18889547440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18889547440 is the 68720-th decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18889547440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22696404480).

18889547440 is an abundant number, since it is smaller than the sum of its proper divisors (26503261520).

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

18889547440 is a wasteful number, since it uses less digits than its factorization.

18889547440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9770 (or 9764 counting only the distinct ones).

The product of its (nonzero) digits is 10321920, while the sum is 58.

The spelling of 18889547440 in words is "eighteen billion, eight hundred eighty-nine million, five hundred forty-seven thousand, four hundred forty".