66126330509 has 2 divisors, whose sum is σ = 66126330510. Its totient is φ = 66126330508.

The previous prime is 66126330503. The next prime is 66126330511. The reversal of 66126330509 is 90503362166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65739421609 + 386908900 = 256397^2 + 19670^2 .

It is a cyclic number.

It is not a de Polignac number, because 66126330509 - 2²⁰ = 66125281933 is a prime.

Together with 66126330511, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66126330503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33063165254 + 33063165255.

It is an arithmetic number, because the mean of its divisors is an integer number (33063165255).

Almost surely, 2^66126330509 is an apocalyptic number.

It is an amenable number.

66126330509 is a deficient number, since it is larger than the sum of its proper divisors (1).

66126330509 is an equidigital number, since it uses as much as digits as its factorization.

66126330509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 174960, while the sum is 41.

The spelling of 66126330509 in words is "sixty-six billion, one hundred twenty-six million, three hundred thirty thousand, five hundred nine".