166639199 has 4 divisors (see below), whose sum is σ = 166715736. Its totient is φ = 166562664.

The previous prime is 166639181. The next prime is 166639223. The reversal of 166639199 is 991936661.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 166639199 - 2²⁴ = 149861983 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 (166639169) 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, 34904 + ... + 39389.

It is an arithmetic number, because the mean of its divisors is an integer number (41678934).

Almost surely, 2^166639199 is an apocalyptic number.

166639199 is a deficient number, since it is larger than the sum of its proper divisors (76537).

166639199 is an equidigital number, since it uses as much as digits as its factorization.

166639199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76536.

The product of its digits is 472392, while the sum is 50.

The square root of 166639199 is about 12908.8806253679. The cubic root of 166639199 is about 550.2909744091.

The spelling of 166639199 in words is "one hundred sixty-six million, six hundred thirty-nine thousand, one hundred ninety-nine".