66332909 has 2 divisors, whose sum is σ = 66332910. Its totient is φ = 66332908.

The previous prime is 66332821. The next prime is 66332923. The reversal of 66332909 is 90923366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65966884 + 366025 = 8122^2 + 605^2 .

It is a cyclic number.

It is not a de Polignac number, because 66332909 - 2¹⁶ = 66267373 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66332939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33166454 + 33166455.

It is an arithmetic number, because the mean of its divisors is an integer number (33166455).

Almost surely, 2^66332909 is an apocalyptic number.

It is an amenable number.

66332909 is a deficient number, since it is larger than the sum of its proper divisors (1).

66332909 is an equidigital number, since it uses as much as digits as its factorization.

66332909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52488, while the sum is 38.

The square root of 66332909 is about 8144.5017649946. The cubic root of 66332909 is about 404.8023401685.

The spelling of 66332909 in words is "sixty-six million, three hundred thirty-two thousand, nine hundred nine".