99999988666665 has 16 divisors (see below), whose sum is σ = 161467871611200. Its totient is φ = 52844030707392.

The previous prime is 99999988666663. The next prime is 99999988666667. The reversal of 99999988666665 is 56666688999999.

It is an interprime number because it is at equal distance from previous prime (99999988666663) and next prime (99999988666667).

It is not a de Polignac number, because 99999988666665 - 2¹ = 99999988666663 is a prime.

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (99999988666663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30581034655 + ... + 30581037924.

It is an arithmetic number, because the mean of its divisors is an integer number (10091741975700).

Almost surely, 2^{99999988666665} is an apocalyptic number.

It is an amenable number.

99999988666665 is a deficient number, since it is larger than the sum of its proper divisors (61467882944535).

99999988666665 is a wasteful number, since it uses less digits than its factorization.

99999988666665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61162072696.

The product of its digits is 1322395269120, while the sum is 105.

The spelling of 99999988666665 in words is "ninety-nine trillion, nine hundred ninety-nine billion, nine hundred eighty-eight million, six hundred sixty-six thousand, six hundred sixty-five".