18899481968640 has 1440 divisors, whose sum is σ = 82523164179456. Its totient is φ = 3894253977600.

The previous prime is 18899481968623. The next prime is 18899481968641. The reversal of 18899481968640 is 4686918499881.

18899481968640 is a `hidden beast` number, since 1 + 8 + 8 + 9 + 9 + 481 + 96 + 8 + 6 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a self number, because there is not a number n which added to its sum of digits gives 18899481968640.

It is not an unprimeable number, because it can be changed into a prime (18899481968641) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2884973365 + ... + 2884979915.

Almost surely, 2^{18899481968640} is an apocalyptic number.

18899481968640 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 18899481968640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41261582089728).

18899481968640 is an abundant number, since it is smaller than the sum of its proper divisors (63623682210816).

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

18899481968640 is a wasteful number, since it uses less digits than its factorization.

18899481968640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6653 (or 6624 counting only the distinct ones).

The product of its (nonzero) digits is 1719926784, while the sum is 81.

The spelling of 18899481968640 in words is "eighteen trillion, eight hundred ninety-nine billion, four hundred eighty-one million, nine hundred sixty-eight thousand, six hundred forty".