66980993 has 2 divisors, whose sum is σ = 66980994. Its totient is φ = 66980992.

The previous prime is 66980959. The next prime is 66980999. The reversal of 66980993 is 39908966.

66980993 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43864129 + 23116864 = 6623^2 + 4808^2 .

It is a cyclic number.

It is not a de Polignac number, because 66980993 - 2⁸ = 66980737 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (66980999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33490496 + 33490497.

It is an arithmetic number, because the mean of its divisors is an integer number (33490497).

Almost surely, 2^66980993 is an apocalyptic number.

It is an amenable number.

66980993 is a deficient number, since it is larger than the sum of its proper divisors (1).

66980993 is an equidigital number, since it uses as much as digits as its factorization.

66980993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 629856, while the sum is 50.

The square root of 66980993 is about 8184.1916522037. The cubic root of 66980993 is about 406.1163995242.

The spelling of 66980993 in words is "sixty-six million, nine hundred eighty thousand, nine hundred ninety-three".