66533544689 has 2 divisors, whose sum is σ = 66533544690. Its totient is φ = 66533544688.

The previous prime is 66533544661. The next prime is 66533544697. The reversal of 66533544689 is 98644533566.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45329816464 + 21203728225 = 212908^2 + 145615^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66533544689 is a prime.

It is not a weakly prime, because it can be changed into another prime (66533544629) 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, 33266772344 + 33266772345.

It is an arithmetic number, because the mean of its divisors is an integer number (33266772345).

Almost surely, 2^66533544689 is an apocalyptic number.

It is an amenable number.

66533544689 is a deficient number, since it is larger than the sum of its proper divisors (1).

66533544689 is an equidigital number, since it uses as much as digits as its factorization.

66533544689 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 55987200, while the sum is 59.

The spelling of 66533544689 in words is "sixty-six billion, five hundred thirty-three million, five hundred forty-four thousand, six hundred eighty-nine".