166851864089 has 2 divisors, whose sum is σ = 166851864090. Its totient is φ = 166851864088.

The previous prime is 166851864041. The next prime is 166851864103. The reversal of 166851864089 is 980468158661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147212644489 + 19639219600 = 383683^2 + 140140^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166851864089 is a prime.

It is not a weakly prime, because it can be changed into another prime (166851864589) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83425932044 + 83425932045.

It is an arithmetic number, because the mean of its divisors is an integer number (83425932045).

Almost surely, 2^166851864089 is an apocalyptic number.

It is an amenable number.

166851864089 is a deficient number, since it is larger than the sum of its proper divisors (1).

166851864089 is an equidigital number, since it uses as much as digits as its factorization.

166851864089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19906560, while the sum is 62.

The spelling of 166851864089 in words is "one hundred sixty-six billion, eight hundred fifty-one million, eight hundred sixty-four thousand, eighty-nine".