9999900099966 has 64 divisors (see below), whose sum is σ = 23284302405120. Its totient is φ = 2804007888000.

The previous prime is 9999900099907. The next prime is 9999900099967. The reversal of 9999900099966 is 6699900099999.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999900099967) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5848285 + ... + 7362216.

It is an arithmetic number, because the mean of its divisors is an integer number (363817225080).

Almost surely, 2^{9999900099966} is an apocalyptic number.

9999900099966 is an abundant number, since it is smaller than the sum of its proper divisors (13284402305154).

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

9999900099966 is a wasteful number, since it uses less digits than its factorization.

9999900099966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13210849.

The product of its (nonzero) digits is 1549681956, while the sum is 84.

The spelling of 9999900099966 in words is "nine trillion, nine hundred ninety-nine billion, nine hundred million, ninety-nine thousand, nine hundred sixty-six".