6699999881 has 2 divisors, whose sum is σ = 6699999882. Its totient is φ = 6699999880.

The previous prime is 6699999877. The next prime is 6699999913. The reversal of 6699999881 is 1889999966.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3924396025 + 2775603856 = 62645^2 + 52684^2 .

It is a cyclic number.

It is not a de Polignac number, because 6699999881 - 2² = 6699999877 is a prime.

It is a super-2 number, since 2×6699999881² = 89779996810800028322, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 6699999799 and 6699999808.

It is not a weakly prime, because it can be changed into another prime (6699999851) 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, 3349999940 + 3349999941.

It is an arithmetic number, because the mean of its divisors is an integer number (3349999941).

Almost surely, 2^6699999881 is an apocalyptic number.

It is an amenable number.

6699999881 is a deficient number, since it is larger than the sum of its proper divisors (1).

6699999881 is an equidigital number, since it uses as much as digits as its factorization.

6699999881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 136048896, while the sum is 74.

The square root of 6699999881 is about 81853.5269918163. The cubic root of 6699999881 is about 1885.2036198598.

The spelling of 6699999881 in words is "six billion, six hundred ninety-nine million, nine hundred ninety-nine thousand, eight hundred eighty-one".