66209287 has 2 divisors, whose sum is σ = 66209288. Its totient is φ = 66209286.

The previous prime is 66209263. The next prime is 66209303. The reversal of 66209287 is 78290266.

66209287 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66209287 - 2⁷ = 66209159 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 (66209587) 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, 33104643 + 33104644.

It is an arithmetic number, because the mean of its divisors is an integer number (33104644).

Almost surely, 2^66209287 is an apocalyptic number.

66209287 is a deficient number, since it is larger than the sum of its proper divisors (1).

66209287 is an equidigital number, since it uses as much as digits as its factorization.

66209287 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 66209287 is about 8136.9089339872. The cubic root of 66209287 is about 404.5507124557.

The spelling of 66209287 in words is "sixty-six million, two hundred nine thousand, two hundred eighty-seven".