9999888886665 has 48 divisors (see below), whose sum is σ = 17683953011712. Its totient is φ = 5225602741632.

The previous prime is 9999888886661. The next prime is 9999888886667. The reversal of 9999888886665 is 5666888889999.

It is not a de Polignac number, because 9999888886665 - 2² = 9999888886661 is a prime.

It is a Curzon number.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (9999888886661) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1049497 + ... + 4593606.

It is an arithmetic number, because the mean of its divisors is an integer number (368415687744).

Almost surely, 2^{9999888886665} is an apocalyptic number.

It is an amenable number.

9999888886665 is a deficient number, since it is larger than the sum of its proper divisors (7684064125047).

9999888886665 is a wasteful number, since it uses less digits than its factorization.

9999888886665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5643910 (or 5643907 counting only the distinct ones).

The product of its digits is 232190115840, while the sum is 99.

The spelling of 9999888886665 in words is "nine trillion, nine hundred ninety-nine billion, eight hundred eighty-eight million, eight hundred eighty-six thousand, six hundred sixty-five".