9939866720 has 192 divisors, whose sum is σ = 28429470720. Its totient is φ = 3208108032.

The previous prime is 9939866711. The next prime is 9939866723. The reversal of 9939866720 is 276689399.

It is a super-2 number, since 2×9939866720² (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 9939866720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9939866723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3552362 + ... + 3555158.

It is an arithmetic number, because the mean of its divisors is an integer number (148070160).

Almost surely, 2^9939866720 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 9939866720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14214735360).

9939866720 is an abundant number, since it is smaller than the sum of its proper divisors (18489604000).

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

9939866720 is a wasteful number, since it uses less digits than its factorization.

9939866720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3005 (or 2997 counting only the distinct ones).

The product of its (nonzero) digits is 8817984, while the sum is 59.

The square root of 9939866720 is about 99698.8802344339. The cubic root of 9939866720 is about 2150.1075641155.

The spelling of 9939866720 in words is "nine billion, nine hundred thirty-nine million, eight hundred sixty-six thousand, seven hundred twenty".