166669180081 has 2 divisors, whose sum is σ = 166669180082. Its totient is φ = 166669180080.

The previous prime is 166669180043. The next prime is 166669180087. The reversal of 166669180081 is 180081966661.

It is a happy number.

166669180081 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., 121510805056 + 45158375025 = 348584^2 + 212505^2 .

It is an emirp because it is prime and its reverse (180081966661) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 180081699991 and 199996180081.

It is a cyclic number.

It is not a de Polignac number, because 166669180081 - 2¹¹ = 166669178033 is a prime.

It is a super-2 number, since 2×166669180081² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (166669180087) 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, 83334590040 + 83334590041.

It is an arithmetic number, because the mean of its divisors is an integer number (83334590041).

Almost surely, 2^166669180081 is an apocalyptic number.

It is an amenable number.

166669180081 is a deficient number, since it is larger than the sum of its proper divisors (1).

166669180081 is an equidigital number, since it uses as much as digits as its factorization.

166669180081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 746496, while the sum is 52.

The spelling of 166669180081 in words is "one hundred sixty-six billion, six hundred sixty-nine million, one hundred eighty thousand, eighty-one".