66241814209 has 2 divisors, whose sum is σ = 66241814210. Its totient is φ = 66241814208.

The previous prime is 66241814207. The next prime is 66241814213. The reversal of 66241814209 is 90241814266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55290819600 + 10950994609 = 235140^2 + 104647^2 .

It is a cyclic number.

It is not a de Polignac number, because 66241814209 - 2¹ = 66241814207 is a prime.

Together with 66241814207, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (66241814207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33120907104 + 33120907105.

It is an arithmetic number, because the mean of its divisors is an integer number (33120907105).

Almost surely, 2^66241814209 is an apocalyptic number.

It is an amenable number.

66241814209 is a deficient number, since it is larger than the sum of its proper divisors (1).

66241814209 is an equidigital number, since it uses as much as digits as its factorization.

66241814209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 165888, while the sum is 43.

The spelling of 66241814209 in words is "sixty-six billion, two hundred forty-one million, eight hundred fourteen thousand, two hundred nine".