20808889947216 has 480 divisors, whose sum is σ = 70382695219200. Its totient is φ = 5606449551360.

The previous prime is 20808889947211. The next prime is 20808889947221. The reversal of 20808889947216 is 61274998880802.

20808889947216 is a `hidden beast` number, since 208 + 0 + 8 + 88 + 99 + 47 + 216 = 666.

It is an interprime number because it is at equal distance from previous prime (20808889947211) and next prime (20808889947221).

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20808889947211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7744282225 + ... + 7744284911.

It is an arithmetic number, because the mean of its divisors is an integer number (146630615040).

Almost surely, 2^{20808889947216} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20808889947216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35191347609600).

20808889947216 is an abundant number, since it is smaller than the sum of its proper divisors (49573805271984).

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

20808889947216 is a wasteful number, since it uses less digits than its factorization.

20808889947216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4447 (or 4438 counting only the distinct ones).

The product of its (nonzero) digits is 222953472, while the sum is 72.

The spelling of 20808889947216 in words is "twenty trillion, eight hundred eight billion, eight hundred eighty-nine million, nine hundred forty-seven thousand, two hundred sixteen".