66066661 has 2 divisors, whose sum is σ = 66066662. Its totient is φ = 66066660.

The previous prime is 66066653. The next prime is 66066677. The reversal of 66066661 is 16666066.

66066661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40564161 + 25502500 = 6369^2 + 5050^2 .

It is a cyclic number.

It is not a de Polignac number, because 66066661 - 2³ = 66066653 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66066661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66060661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33033330 + 33033331.

It is an arithmetic number, because the mean of its divisors is an integer number (33033331).

Almost surely, 2^66066661 is an apocalyptic number.

It is an amenable number.

66066661 is a deficient number, since it is larger than the sum of its proper divisors (1).

66066661 is an equidigital number, since it uses as much as digits as its factorization.

66066661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 66066661 is about 8128.1400701514. The cubic root of 66066661 is about 404.2600134030.

The spelling of 66066661 in words is "sixty-six million, sixty-six thousand, six hundred sixty-one".