166440189 has 4 divisors (see below), whose sum is σ = 221920256. Its totient is φ = 110960124.

The previous prime is 166440187. The next prime is 166440191. The reversal of 166440189 is 981044661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (166440187) and next prime (166440191).

It is not a de Polignac number, because 166440189 - 2¹ = 166440187 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166440181) 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, 27740029 + ... + 27740034.

It is an arithmetic number, because the mean of its divisors is an integer number (55480064).

Almost surely, 2^166440189 is an apocalyptic number.

It is an amenable number.

166440189 is a deficient number, since it is larger than the sum of its proper divisors (55480067).

166440189 is an equidigital number, since it uses as much as digits as its factorization.

166440189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55480066.

The product of its (nonzero) digits is 41472, while the sum is 39.

The square root of 166440189 is about 12901.1700632152. The cubic root of 166440189 is about 550.0718242289.

The spelling of 166440189 in words is "one hundred sixty-six million, four hundred forty thousand, one hundred eighty-nine".