999988111886666 has 16 divisors (see below), whose sum is σ = 1735964895863040. Its totient is φ = 423141443365680.

The previous prime is 999988111886639. The next prime is 999988111886669. The reversal of 999988111886666 is 666688111889999.

999988111886666 is a strobogrammatic number because it is the same when read upside-down.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (999988111886669) 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 7 ways as a sum of consecutive naturals, for example, 452074190525 + ... + 452074192736.

It is an arithmetic number, because the mean of its divisors is an integer number (108497805991440).

Almost surely, 2^{999988111886666} is an apocalyptic number.

999988111886666 is a deficient number, since it is larger than the sum of its proper divisors (735976783976374).

999988111886666 is a wasteful number, since it uses less digits than its factorization.

999988111886666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904148383349.

The product of its digits is 34828517376, while the sum is 95.

The spelling of 999988111886666 in words is "nine hundred ninety-nine trillion, nine hundred eighty-eight billion, one hundred eleven million, eight hundred eighty-six thousand, six hundred sixty-six".