66241709 has 2 divisors, whose sum is σ = 66241710. Its totient is φ = 66241708.

The previous prime is 66241687. The next prime is 66241711. The reversal of 66241709 is 90714266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49308484 + 16933225 = 7022^2 + 4115^2 .

It is a cyclic number.

It is not a de Polignac number, because 66241709 - 2²⁰ = 65193133 is a prime.

It is a super-2 number, since 2×66241709² = 8775928022481362, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 66241711, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66241789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33120854 + 33120855.

It is an arithmetic number, because the mean of its divisors is an integer number (33120855).

Almost surely, 2^66241709 is an apocalyptic number.

It is an amenable number.

66241709 is a deficient number, since it is larger than the sum of its proper divisors (1).

66241709 is an equidigital number, since it uses as much as digits as its factorization.

66241709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 35.

The square root of 66241709 is about 8138.9009700327. The cubic root of 66241709 is about 404.6167364401.

The spelling of 66241709 in words is "sixty-six million, two hundred forty-one thousand, seven hundred nine".