66908161 has 2 divisors, whose sum is σ = 66908162. Its totient is φ = 66908160.

The previous prime is 66908131. The next prime is 66908167. The reversal of 66908161 is 16180966.

66908161 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., 37271025 + 29637136 = 6105^2 + 5444^2 .

It is a cyclic number.

It is not a de Polignac number, because 66908161 - 2¹¹ = 66906113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 66908161.

It is not a weakly prime, because it can be changed into another prime (66908167) 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, 33454080 + 33454081.

It is an arithmetic number, because the mean of its divisors is an integer number (33454081).

Almost surely, 2^66908161 is an apocalyptic number.

It is an amenable number.

66908161 is a deficient number, since it is larger than the sum of its proper divisors (1).

66908161 is an equidigital number, since it uses as much as digits as its factorization.

66908161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 66908161 is about 8179.7408883167. The cubic root of 66908161 is about 405.9691488120.

The spelling of 66908161 in words is "sixty-six million, nine hundred eight thousand, one hundred sixty-one".