79664567999 has 16 divisors (see below), whose sum is σ = 81705231360. Its totient is φ = 77651700000.

The previous prime is 79664567959. The next prime is 79664568007. The reversal of 79664567999 is 99976546697.

It is a cyclic number.

It is not a de Polignac number, because 79664567999 - 2⁸ = 79664567743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79664567909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5148224 + ... + 5163674.

It is an arithmetic number, because the mean of its divisors is an integer number (5106576960).

Almost surely, 2^79664567999 is an apocalyptic number.

79664567999 is a deficient number, since it is larger than the sum of its proper divisors (2040663361).

79664567999 is a wasteful number, since it uses less digits than its factorization.

79664567999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16342.

The product of its digits is 1388832480, while the sum is 77.

The spelling of 79664567999 in words is "seventy-nine billion, six hundred sixty-four million, five hundred sixty-seven thousand, nine hundred ninety-nine".