166380909 has 4 divisors (see below), whose sum is σ = 221841216. Its totient is φ = 110920604.

The previous prime is 166380871. The next prime is 166380959. The reversal of 166380909 is 909083661.

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, and also an emirpimes, since its reverse is a distinct semiprime: 909083661 = 3 ⋅303027887.

It is a cyclic number.

It is not a de Polignac number, because 166380909 - 2¹² = 166376813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166380959) 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, 27730149 + ... + 27730154.

It is an arithmetic number, because the mean of its divisors is an integer number (55460304).

Almost surely, 2^166380909 is an apocalyptic number.

It is an amenable number.

166380909 is a deficient number, since it is larger than the sum of its proper divisors (55460307).

166380909 is an equidigital number, since it uses as much as digits as its factorization.

166380909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55460306.

The product of its (nonzero) digits is 69984, while the sum is 42.

The square root of 166380909 is about 12898.8723925776. The cubic root of 166380909 is about 550.0065112177.

The spelling of 166380909 in words is "one hundred sixty-six million, three hundred eighty thousand, nine hundred nine".