999988888886666 has 64 divisors (see below), whose sum is σ = 1719919979447040. Its totient is φ = 427155813826560.

The previous prime is 999988888886641. The next prime is 999988888886677. The reversal of 999988888886666 is 666688888889999.

999988888886666 is a strobogrammatic number because it is the same when read upside-down.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 75113708426 + ... + 75113721738.

It is an arithmetic number, because the mean of its divisors is an integer number (26873749678860).

Almost surely, 2^{999988888886666} is an apocalyptic number.

999988888886666 is a deficient number, since it is larger than the sum of its proper divisors (719931090560374).

999988888886666 is a wasteful number, since it uses less digits than its factorization.

999988888886666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27519.

The product of its digits is 17832200896512, while the sum is 116.

The spelling of 999988888886666 in words is "nine hundred ninety-nine trillion, nine hundred eighty-eight billion, eight hundred eighty-eight million, eight hundred eighty-six thousand, six hundred sixty-six".