6688888999 has 16 divisors (see below), whose sum is σ = 7307413120. Its totient is φ = 6085497600.

The previous prime is 6688888981. The next prime is 6688889021. The reversal of 6688888999 is 9998888866.

It is a happy number.

It is not a de Polignac number, because 6688888999 - 2¹⁵ = 6688856231 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (79).

It is a Duffinian number.

It is a plaindrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6688888099) 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, 611809 + ... + 622645.

It is an arithmetic number, because the mean of its divisors is an integer number (456713320).

Almost surely, 2^6688888999 is an apocalyptic number.

6688888999 is a deficient number, since it is larger than the sum of its proper divisors (618524121).

6688888999 is a wasteful number, since it uses less digits than its factorization.

6688888999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11530.

The product of its digits is 859963392, while the sum is 79.

The square root of 6688888999 is about 81785.6283157377. The cubic root of 6688888999 is about 1884.1609400238.

The spelling of 6688888999 in words is "six billion, six hundred eighty-eight million, eight hundred eighty-eight thousand, nine hundred ninety-nine".