6628564909 has 2 divisors, whose sum is σ = 6628564910. Its totient is φ = 6628564908.

The previous prime is 6628564883. The next prime is 6628564933. The reversal of 6628564909 is 9094658266.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4110733225 + 2517831684 = 64115^2 + 50178^2 .

It is a cyclic number.

It is not a de Polignac number, because 6628564909 - 2⁷ = 6628564781 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6628564909.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6628564009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3314282454 + 3314282455.

It is an arithmetic number, because the mean of its divisors is an integer number (3314282455).

Almost surely, 2^6628564909 is an apocalyptic number.

It is an amenable number.

6628564909 is a deficient number, since it is larger than the sum of its proper divisors (1).

6628564909 is an equidigital number, since it uses as much as digits as its factorization.

6628564909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5598720, while the sum is 55.

The square root of 6628564909 is about 81415.9990972290. Note that the first 3 decimals coincide. The cubic root of 6628564909 is about 1878.4796926010.

The spelling of 6628564909 in words is "six billion, six hundred twenty-eight million, five hundred sixty-four thousand, nine hundred nine".