66660549979 has 2 divisors, whose sum is σ = 66660549980. Its totient is φ = 66660549978.

The previous prime is 66660549877. The next prime is 66660550001. The reversal of 66660549979 is 97994506666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66660549979 - 2¹¹ = 66660547931 is a prime.

It is not a weakly prime, because it can be changed into another prime (66660543979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33330274989 + 33330274990.

It is an arithmetic number, because the mean of its divisors is an integer number (33330274990).

Almost surely, 2^66660549979 is an apocalyptic number.

66660549979 is a deficient number, since it is larger than the sum of its proper divisors (1).

66660549979 is an equidigital number, since it uses as much as digits as its factorization.

66660549979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 132269760, while the sum is 67.

The spelling of 66660549979 in words is "sixty-six billion, six hundred sixty million, five hundred forty-nine thousand, nine hundred seventy-nine".