66213826577 has 2 divisors, whose sum is σ = 66213826578. Its totient is φ = 66213826576.

The previous prime is 66213826517. The next prime is 66213826589. The reversal of 66213826577 is 77562831266.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62555512321 + 3658314256 = 250111^2 + 60484^2 .

It is a cyclic number.

It is not a de Polignac number, because 66213826577 - 2⁸ = 66213826321 is a prime.

It is not a weakly prime, because it can be changed into another prime (66213826517) 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, 33106913288 + 33106913289.

It is an arithmetic number, because the mean of its divisors is an integer number (33106913289).

Almost surely, 2^66213826577 is an apocalyptic number.

It is an amenable number.

66213826577 is a deficient number, since it is larger than the sum of its proper divisors (1).

66213826577 is an equidigital number, since it uses as much as digits as its factorization.

66213826577 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5080320, while the sum is 53.

The spelling of 66213826577 in words is "sixty-six billion, two hundred thirteen million, eight hundred twenty-six thousand, five hundred seventy-seven".