6688888931 has 2 divisors, whose sum is σ = 6688888932. Its totient is φ = 6688888930.

The previous prime is 6688888883. The next prime is 6688888961. The reversal of 6688888931 is 1398888866.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6688888931 is a prime.

It is a super-2 number, since 2×6688888931² = 89482470262508645522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6688888961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3344444465 + 3344444466.

It is an arithmetic number, because the mean of its divisors is an integer number (3344444466).

Almost surely, 2^6688888931 is an apocalyptic number.

6688888931 is a deficient number, since it is larger than the sum of its proper divisors (1).

6688888931 is an equidigital number, since it uses as much as digits as its factorization.

6688888931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31850496, while the sum is 65.

The square root of 6688888931 is about 81785.6279000168. The cubic root of 6688888931 is about 1884.1609336389.

Subtracting from 6688888931 its sum of digits (65), we obtain a palindrome (6688888866).

The spelling of 6688888931 in words is "six billion, six hundred eighty-eight million, eight hundred eighty-eight thousand, nine hundred thirty-one".