66328364555591 has 2 divisors, whose sum is σ = 66328364555592. Its totient is φ = 66328364555590.

The previous prime is 66328364555513. The next prime is 66328364555671. The reversal of 66328364555591 is 19555546382366.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66328364555591 - 2¹⁴ = 66328364539207 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66328364551591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33164182277795 + 33164182277796.

It is an arithmetic number, because the mean of its divisors is an integer number (33164182277796).

Almost surely, 2^{66328364555591} is an apocalyptic number.

66328364555591 is a deficient number, since it is larger than the sum of its proper divisors (1).

66328364555591 is an equidigital number, since it uses as much as digits as its factorization.

66328364555591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 699840000, while the sum is 68.

The spelling of 66328364555591 in words is "sixty-six trillion, three hundred twenty-eight billion, three hundred sixty-four million, five hundred fifty-five thousand, five hundred ninety-one".