6406666009 has 2 divisors, whose sum is σ = 6406666010. Its totient is φ = 6406666008.

The previous prime is 6406665997. The next prime is 6406666117. The reversal of 6406666009 is 9006666046.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3798010384 + 2608655625 = 61628^2 + 51075^2 .

It is a cyclic number.

It is not a de Polignac number, because 6406666009 - 2⁵ = 6406665977 is a prime.

It is not a weakly prime, because it can be changed into another prime (6406666909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3203333004 + 3203333005.

It is an arithmetic number, because the mean of its divisors is an integer number (3203333005).

Almost surely, 2^6406666009 is an apocalyptic number.

It is an amenable number.

6406666009 is a deficient number, since it is larger than the sum of its proper divisors (1).

6406666009 is an equidigital number, since it uses as much as digits as its factorization.

6406666009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 43.

The square root of 6406666009 is about 80041.6517133423. The cubic root of 6406666009 is about 1857.2799112962.

The spelling of 6406666009 in words is "six billion, four hundred six million, six hundred sixty-six thousand, nine".