6688880888861 has 2 divisors, whose sum is σ = 6688880888862. Its totient is φ = 6688880888860.

The previous prime is 6688880888819. The next prime is 6688880888863. The reversal of 6688880888861 is 1688880888866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6410107448761 + 278773440100 = 2531819^2 + 527990^2 .

It is a cyclic number.

It is not a de Polignac number, because 6688880888861 - 2²⁶ = 6688813779997 is a prime.

It is a super-2 number, since 2×6688880888861² (a number of 26 digits) contains 22 as substring.

Together with 6688880888863, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6688880888861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6688880888863) 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 as a sum of consecutive naturals, namely, 3344440444430 + 3344440444431.

It is an arithmetic number, because the mean of its divisors is an integer number (3344440444431).

Almost surely, 2^{6688880888861} is an apocalyptic number.

It is an amenable number.

6688880888861 is a deficient number, since it is larger than the sum of its proper divisors (1).

6688880888861 is an equidigital number, since it uses as much as digits as its factorization.

6688880888861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3623878656, while the sum is 83.

The spelling of 6688880888861 in words is "six trillion, six hundred eighty-eight billion, eight hundred eighty million, eight hundred eighty-eight thousand, eight hundred sixty-one".