16666666666665 has 32 divisors (see below), whose sum is σ = 27513733086720. Its totient is φ = 8610779364096.

The previous prime is 16666666666649. The next prime is 16666666666673. The reversal of 16666666666665 is 56666666666661.

It is not a de Polignac number, because 16666666666665 - 2⁴ = 16666666666649 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 132623022 + ... + 132748631.

It is an arithmetic number, because the mean of its divisors is an integer number (859804158960).

Almost surely, 2^{16666666666665} is an apocalyptic number.

16666666666665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

16666666666665 is a deficient number, since it is larger than the sum of its proper divisors (10847066420055).

16666666666665 is a wasteful number, since it uses less digits than its factorization.

16666666666665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265371793.

The product of its digits is 10883911680, while the sum is 78.

It can be divided in two parts, 1 and 6666666666665, that added together give a palindrome (6666666666666).

The spelling of 16666666666665 in words is "sixteen trillion, six hundred sixty-six billion, six hundred sixty-six million, six hundred sixty-six thousand, six hundred sixty-five".