18665358784800 has 576 divisors, whose sum is σ = 74867225690880. Its totient is φ = 3933396910080.

The previous prime is 18665358784789. The next prime is 18665358784811. The reversal of 18665358784800 is 848785356681.

It is an interprime number because it is at equal distance from previous prime (18665358784789) and next prime (18665358784811).

It is a super-2 number, since 2×18665358784800² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (69) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 181002054 + ... + 181105146.

It is an arithmetic number, because the mean of its divisors is an integer number (129977822380).

Almost surely, 2^{18665358784800} is an apocalyptic number.

18665358784800 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 18665358784800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37433612845440).

18665358784800 is an abundant number, since it is smaller than the sum of its proper divisors (56201866906080).

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

18665358784800 is a wasteful number, since it uses less digits than its factorization.

18665358784800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103965 (or 103952 counting only the distinct ones).

The product of its (nonzero) digits is 309657600, while the sum is 69.

The spelling of 18665358784800 in words is "eighteen trillion, six hundred sixty-five billion, three hundred fifty-eight million, seven hundred eighty-four thousand, eight hundred".