18443515968 has 560 divisors, whose sum is σ = 61534877184. Its totient is φ = 5434490880.

The previous prime is 18443515967. The next prime is 18443516041. The reversal of 18443515968 is 86951534481.

It is a happy number.

18443515968 is a `hidden beast` number, since 1 + 8 + 4 + 43 + 5 + 1 + 596 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18443515967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 117474546 + ... + 117474702.

Almost surely, 2^18443515968 is an apocalyptic number.

18443515968 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 18443515968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30767438592).

18443515968 is an abundant number, since it is smaller than the sum of its proper divisors (43091361216).

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

18443515968 is a wasteful number, since it uses less digits than its factorization.

18443515968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272 (or 253 counting only the distinct ones).

The product of its digits is 4147200, while the sum is 54.

The spelling of 18443515968 in words is "eighteen billion, four hundred forty-three million, five hundred fifteen thousand, nine hundred sixty-eight".