66684067799 has 2 divisors, whose sum is σ = 66684067800. Its totient is φ = 66684067798.

The previous prime is 66684067789. The next prime is 66684067819. The reversal of 66684067799 is 99776048666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66684067799 - 2¹² = 66684063703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66684067759) 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, 33342033899 + 33342033900.

It is an arithmetic number, because the mean of its divisors is an integer number (33342033900).

Almost surely, 2^66684067799 is an apocalyptic number.

66684067799 is a deficient number, since it is larger than the sum of its proper divisors (1).

66684067799 is an equidigital number, since it uses as much as digits as its factorization.

66684067799 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 164602368, while the sum is 68.

The spelling of 66684067799 in words is "sixty-six billion, six hundred eighty-four million, sixty-seven thousand, seven hundred ninety-nine".