166445312213 has 4 divisors (see below), whose sum is σ = 166891546668. Its totient is φ = 165999077760.

The previous prime is 166445312207. The next prime is 166445312227. The reversal of 166445312213 is 312213544661.

166445312213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 45451255249 + 120994056964 = 213193^2 + 347842^2 .

It is a cyclic number.

It is not a de Polignac number, because 166445312213 - 2⁶ = 166445312149 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166445312203) 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 in 3 ways as a sum of consecutive naturals, for example, 223116668 + ... + 223117413.

It is an arithmetic number, because the mean of its divisors is an integer number (41722886667).

Almost surely, 2^166445312213 is an apocalyptic number.

It is an amenable number.

166445312213 is a deficient number, since it is larger than the sum of its proper divisors (446234455).

166445312213 is an equidigital number, since it uses as much as digits as its factorization.

166445312213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446234454.

The product of its digits is 103680, while the sum is 38.

Adding to 166445312213 its reverse (312213544661), we get a palindrome (478658856874).

The spelling of 166445312213 in words is "one hundred sixty-six billion, four hundred forty-five million, three hundred twelve thousand, two hundred thirteen".