66636013 has 2 divisors, whose sum is σ = 66636014. Its totient is φ = 66636012.

The previous prime is 66636007. The next prime is 66636041. The reversal of 66636013 is 31063666.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66634569 + 1444 = 8163^2 + 38^2 .

It is a cyclic number.

It is not a de Polignac number, because 66636013 - 2⁹ = 66635501 is a prime.

It is equal to p_3931591 and since 66636013 and 3931591 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66636043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33318006 + 33318007.

It is an arithmetic number, because the mean of its divisors is an integer number (33318007).

Almost surely, 2^66636013 is an apocalyptic number.

It is an amenable number.

66636013 is a deficient number, since it is larger than the sum of its proper divisors (1).

66636013 is an equidigital number, since it uses as much as digits as its factorization.

66636013 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 31.

The square root of 66636013 is about 8163.0884473954. The cubic root of 66636013 is about 405.4179762464.

Adding to 66636013 its reverse (31063666), we get a palindrome (97699679).

The spelling of 66636013 in words is "sixty-six million, six hundred thirty-six thousand, thirteen".