9989785566720 has 480 divisors, whose sum is σ = 34834271142528. Its totient is φ = 2645771157504.

The previous prime is 9989785566613. The next prime is 9989785566727. The reversal of 9989785566720 is 276655879899.

9989785566720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (480).

It is a self number, because there is not a number n which added to its sum of digits gives 9989785566720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9989785566727) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2173107462 + ... + 2173112058.

Almost surely, 2^{9989785566720} is an apocalyptic number.

9989785566720 is a gapful number since it is divisible by the number (90) 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 9989785566720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17417135571264).

9989785566720 is an abundant number, since it is smaller than the sum of its proper divisors (24844485575808).

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

9989785566720 is a wasteful number, since it uses less digits than its factorization.

9989785566720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5250 (or 5231 counting only the distinct ones).

The product of its (nonzero) digits is 4115059200, while the sum is 81.

The spelling of 9989785566720 in words is "nine trillion, nine hundred eighty-nine billion, seven hundred eighty-five million, five hundred sixty-six thousand, seven hundred twenty".