6609968681 has 2 divisors, whose sum is σ = 6609968682. Its totient is φ = 6609968680.

The previous prime is 6609968669. The next prime is 6609968749. The reversal of 6609968681 is 1868699066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6605625625 + 4343056 = 81275^2 + 2084^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6609968681 is a prime.

It is a super-3 number, since 3×6609968681³ (a number of 30 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 6609968681.

It is not a weakly prime, because it can be changed into another prime (6609968641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3304984340 + 3304984341.

It is an arithmetic number, because the mean of its divisors is an integer number (3304984341).

Almost surely, 2^6609968681 is an apocalyptic number.

It is an amenable number.

6609968681 is a deficient number, since it is larger than the sum of its proper divisors (1).

6609968681 is an equidigital number, since it uses as much as digits as its factorization.

6609968681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6718464, while the sum is 59.

The square root of 6609968681 is about 81301.7138872238. The cubic root of 6609968681 is about 1876.7213755990.

The spelling of 6609968681 in words is "six billion, six hundred nine million, nine hundred sixty-eight thousand, six hundred eighty-one".