18097821504 has 336 divisors, whose sum is σ = 61813440000. Its totient is φ = 5058192384.

The previous prime is 18097821491. The next prime is 18097821509. The reversal of 18097821504 is 40512879081.

It is a tau number, because it is divible by the number of its divisors (336).

It is a super-2 number, since 2×18097821504² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18097821504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18097821509) 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 47 ways as a sum of consecutive naturals, for example, 9284722 + ... + 9286670.

Almost surely, 2^18097821504 is an apocalyptic number.

18097821504 is a gapful number since it is divisible by the number (14) 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 18097821504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30906720000).

18097821504 is an abundant number, since it is smaller than the sum of its proper divisors (43715618496).

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

18097821504 is a wasteful number, since it uses less digits than its factorization.

18097821504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2035 (or 2008 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 18097821504 in words is "eighteen billion, ninety-seven million, eight hundred twenty-one thousand, five hundred four".