9999966101920 has 96 divisors (see below), whose sum is σ = 24039879192000. Its totient is φ = 3929810835456.

The previous prime is 9999966101911. The next prime is 9999966101953. The reversal of 9999966101920 is 291016699999.

It is a self number, because there is not a number n which added to its sum of digits gives 9999966101920.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 15322431 + ... + 15961729.

It is an arithmetic number, because the mean of its divisors is an integer number (250415408250).

Almost surely, 2^{9999966101920} 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 9999966101920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12019939596000).

9999966101920 is an abundant number, since it is smaller than the sum of its proper divisors (14039913090080).

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

9999966101920 is a wasteful number, since it uses less digits than its factorization.

9999966101920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641030 (or 641022 counting only the distinct ones).

The product of its (nonzero) digits is 38263752, while the sum is 70.

The spelling of 9999966101920 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred sixty-six million, one hundred one thousand, nine hundred twenty".