18208921573440 has 1792 divisors, whose sum is σ = 73471147545600. Its totient is φ = 4213820620800.

The previous prime is 18208921573391. The next prime is 18208921573459. The reversal of 18208921573440 is 4437512980281.

18208921573440 is a `hidden beast` number, since 1 + 8 + 2 + 0 + 8 + 9 + 21 + 573 + 4 + 40 = 666.

It is a super-3 number, since 3×18208921573440³ (a number of 41 digits) contains 333 as substring.

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

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 255 ways as a sum of consecutive naturals, for example, 22452430635 + ... + 22452431445.

It is an arithmetic number, because the mean of its divisors is an integer number (40999524300).

Almost surely, 2^{18208921573440} is an apocalyptic number.

18208921573440 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 18208921573440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36735573772800).

18208921573440 is an abundant number, since it is smaller than the sum of its proper divisors (55262225972160).

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

18208921573440 is a wasteful number, since it uses less digits than its factorization.

18208921573440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1053 (or 1037 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 54.

The spelling of 18208921573440 in words is "eighteen trillion, two hundred eight billion, nine hundred twenty-one million, five hundred seventy-three thousand, four hundred forty".