166138427 has 16 divisors (see below), whose sum is σ = 205867200. Its totient is φ = 130557312.

The previous prime is 166138417. The next prime is 166138439. The reversal of 166138427 is 724831661.

It is a cyclic number.

It is not a de Polignac number, because 166138427 - 2⁸ = 166138171 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (166138417) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7433 + ... + 19685.

It is an arithmetic number, because the mean of its divisors is an integer number (12866700).

Almost surely, 2^166138427 is an apocalyptic number.

166138427 is a deficient number, since it is larger than the sum of its proper divisors (39728773).

166138427 is a wasteful number, since it uses less digits than its factorization.

166138427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12422.

The product of its digits is 48384, while the sum is 38.

The square root of 166138427 is about 12889.4696167065. The cubic root of 166138427 is about 549.7391898419.

The spelling of 166138427 in words is "one hundred sixty-six million, one hundred thirty-eight thousand, four hundred twenty-seven".