166744091 has 4 divisors (see below), whose sum is σ = 167084184. Its totient is φ = 166404000.

The previous prime is 166744079. The next prime is 166744093. The reversal of 166744091 is 190447661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190447661 = 1039 ⋅183299.

It is a cyclic number.

It is not a de Polignac number, because 166744091 - 2⁶ = 166744027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166744093) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169310 + ... + 170291.

It is an arithmetic number, because the mean of its divisors is an integer number (41771046).

Almost surely, 2^166744091 is an apocalyptic number.

166744091 is a deficient number, since it is larger than the sum of its proper divisors (340093).

166744091 is an equidigital number, since it uses as much as digits as its factorization.

166744091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340092.

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 166744091 is about 12912.9427707243. The cubic root of 166744091 is about 550.4064114622.

The spelling of 166744091 in words is "one hundred sixty-six million, seven hundred forty-four thousand, ninety-one".