66755055761 has 2 divisors, whose sum is σ = 66755055762. Its totient is φ = 66755055760.

The previous prime is 66755055743. The next prime is 66755055781. The reversal of 66755055761 is 16755055766.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66141552400 + 613503361 = 257180^2 + 24769^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66755055761 is a prime.

It is not a weakly prime, because it can be changed into another prime (66755055781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33377527880 + 33377527881.

It is an arithmetic number, because the mean of its divisors is an integer number (33377527881).

Almost surely, 2^66755055761 is an apocalyptic number.

It is an amenable number.

66755055761 is a deficient number, since it is larger than the sum of its proper divisors (1).

66755055761 is an equidigital number, since it uses as much as digits as its factorization.

66755055761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6615000, while the sum is 53.

The spelling of 66755055761 in words is "sixty-six billion, seven hundred fifty-five million, fifty-five thousand, seven hundred sixty-one".