66385633 has 2 divisors, whose sum is σ = 66385634. Its totient is φ = 66385632.

The previous prime is 66385603. The next prime is 66385643. The reversal of 66385633 is 33658366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44930209 + 21455424 = 6703^2 + 4632^2 .

It is a cyclic number.

It is not a de Polignac number, because 66385633 - 2¹⁷ = 66254561 is a prime.

It is not a weakly prime, because it can be changed into another prime (66385603) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33192816 + 33192817.

It is an arithmetic number, because the mean of its divisors is an integer number (33192817).

Almost surely, 2^66385633 is an apocalyptic number.

It is an amenable number.

66385633 is a deficient number, since it is larger than the sum of its proper divisors (1).

66385633 is an equidigital number, since it uses as much as digits as its factorization.

66385633 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 233280, while the sum is 40.

The square root of 66385633 is about 8147.7379069285. The cubic root of 66385633 is about 404.9095626955.

The spelling of 66385633 in words is "sixty-six million, three hundred eighty-five thousand, six hundred thirty-three".