66066647 has 2 divisors, whose sum is σ = 66066648. Its totient is φ = 66066646.

The previous prime is 66066643. The next prime is 66066653. The reversal of 66066647 is 74666066.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66066647 - 2² = 66066643 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66066643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33033323 + 33033324.

It is an arithmetic number, because the mean of its divisors is an integer number (33033324).

Almost surely, 2^66066647 is an apocalyptic number.

66066647 is a deficient number, since it is larger than the sum of its proper divisors (1).

66066647 is an equidigital number, since it uses as much as digits as its factorization.

66066647 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 41.

The square root of 66066647 is about 8128.1392089457. The cubic root of 66066647 is about 404.2599848478.

The spelling of 66066647 in words is "sixty-six million, sixty-six thousand, six hundred forty-seven".