166564897 has 2 divisors, whose sum is σ = 166564898. Its totient is φ = 166564896.

The previous prime is 166564889. The next prime is 166564907. The reversal of 166564897 is 798465661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 147476736 + 19088161 = 12144^2 + 4369^2 .

It is a cyclic number.

It is not a de Polignac number, because 166564897 - 2³ = 166564889 is a prime.

It is not a weakly prime, because it can be changed into another prime (166567897) 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, 83282448 + 83282449.

It is an arithmetic number, because the mean of its divisors is an integer number (83282449).

Almost surely, 2^166564897 is an apocalyptic number.

It is an amenable number.

166564897 is a deficient number, since it is larger than the sum of its proper divisors (1).

166564897 is an equidigital number, since it uses as much as digits as its factorization.

166564897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2177280, while the sum is 52.

The square root of 166564897 is about 12906.0023632417. The cubic root of 166564897 is about 550.2091733307.

The spelling of 166564897 in words is "one hundred sixty-six million, five hundred sixty-four thousand, eight hundred ninety-seven".