166566501 has 6 divisors (see below), whose sum is σ = 240596070. Its totient is φ = 111044328.

The previous prime is 166566487. The next prime is 166566571. The reversal of 166566501 is 105665661.

It can be written as a sum of positive squares in only one way, i.e., 162562500 + 4004001 = 12750^2 + 2001^2 .

It is not a de Polignac number, because 166566501 - 2⁷ = 166566373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166566571) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9253686 + ... + 9253703.

It is an arithmetic number, because the mean of its divisors is an integer number (40099345).

Almost surely, 2^166566501 is an apocalyptic number.

It is an amenable number.

166566501 is a deficient number, since it is larger than the sum of its proper divisors (74029569).

166566501 is a wasteful number, since it uses less digits than its factorization.

166566501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18507395 (or 18507392 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 166566501 is about 12906.0645047203. The cubic root of 166566501 is about 550.2109394745.

The spelling of 166566501 in words is "one hundred sixty-six million, five hundred sixty-six thousand, five hundred one".