18381218548 has 24 divisors (see below), whose sum is σ = 40104477504. Its totient is φ = 7161513600.

The previous prime is 18381218539. The next prime is 18381218549. The reversal of 18381218548 is 84581218381.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18381218549) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 29839333 + ... + 29839948.

It is an arithmetic number, because the mean of its divisors is an integer number (1671019896).

Almost surely, 2^18381218548 is an apocalyptic number.

It is an amenable number.

18381218548 is an abundant number, since it is smaller than the sum of its proper divisors (21723258956).

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

18381218548 is a wasteful number, since it uses less digits than its factorization.

18381218548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59679303 (or 59679301 counting only the distinct ones).

The product of its digits is 491520, while the sum is 49.

The spelling of 18381218548 in words is "eighteen billion, three hundred eighty-one million, two hundred eighteen thousand, five hundred forty-eight".