66124081217 has 2 divisors, whose sum is σ = 66124081218. Its totient is φ = 66124081216.

The previous prime is 66124081207. The next prime is 66124081307. The reversal of 66124081217 is 71218042166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62118583696 + 4005497521 = 249236^2 + 63289^2 .

It is a cyclic number.

It is not a de Polignac number, because 66124081217 - 2¹² = 66124077121 is a prime.

It is not a weakly prime, because it can be changed into another prime (66124081207) 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, 33062040608 + 33062040609.

It is an arithmetic number, because the mean of its divisors is an integer number (33062040609).

Almost surely, 2^66124081217 is an apocalyptic number.

It is an amenable number.

66124081217 is a deficient number, since it is larger than the sum of its proper divisors (1).

66124081217 is an equidigital number, since it uses as much as digits as its factorization.

66124081217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32256, while the sum is 38.

The spelling of 66124081217 in words is "sixty-six billion, one hundred twenty-four million, eighty-one thousand, two hundred seventeen".