66730651717 has 2 divisors, whose sum is σ = 66730651718. Its totient is φ = 66730651716.

The previous prime is 66730651681. The next prime is 66730651829. The reversal of 66730651717 is 71715603766.

It is a happy number.

66730651717 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., 66538718401 + 191933316 = 257951^2 + 13854^2 .

It is a cyclic number.

It is not a de Polignac number, because 66730651717 - 2²⁷ = 66596433989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66730654717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33365325858 + 33365325859.

It is an arithmetic number, because the mean of its divisors is an integer number (33365325859).

Almost surely, 2^66730651717 is an apocalyptic number.

It is an amenable number.

66730651717 is a deficient number, since it is larger than the sum of its proper divisors (1).

66730651717 is an equidigital number, since it uses as much as digits as its factorization.

66730651717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1111320, while the sum is 49.

The spelling of 66730651717 in words is "sixty-six billion, seven hundred thirty million, six hundred fifty-one thousand, seven hundred seventeen".