166205005 has 16 divisors (see below), whose sum is σ = 211526640. Its totient is φ = 124936192.

The previous prime is 166204993. The next prime is 166205009. The reversal of 166205005 is 500502661.

It can be written as a sum of positive squares in 8 ways, for example, as 53611684 + 112593321 = 7322^2 + 10611^2 .

It is a cyclic number.

It is not a de Polignac number, because 166205005 - 2¹¹ = 166202957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166205009) 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 in 15 ways as a sum of consecutive naturals, for example, 67557 + ... + 69973.

It is an arithmetic number, because the mean of its divisors is an integer number (13220415).

Almost surely, 2^166205005 is an apocalyptic number.

It is an amenable number.

166205005 is a deficient number, since it is larger than the sum of its proper divisors (45321635).

166205005 is a wasteful number, since it uses less digits than its factorization.

166205005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3248.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 166205005 is about 12892.0520088929. The cubic root of 166205005 is about 549.8126138503.

Adding to 166205005 its reverse (500502661), we get a palindrome (666707666).

The spelling of 166205005 in words is "one hundred sixty-six million, two hundred five thousand, five".