166058921 has 4 divisors (see below), whose sum is σ = 189781632. Its totient is φ = 142336212.

The previous prime is 166058903. The next prime is 166058939. The reversal of 166058921 is 129850661.

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 (166058903) and next prime (166058939).

It is a cyclic number.

It is not a de Polignac number, because 166058921 - 2¹⁰ = 166057897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166058021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11861345 + ... + 11861358.

It is an arithmetic number, because the mean of its divisors is an integer number (47445408).

Almost surely, 2^166058921 is an apocalyptic number.

It is an amenable number.

166058921 is a deficient number, since it is larger than the sum of its proper divisors (23722711).

166058921 is an equidigital number, since it uses as much as digits as its factorization.

166058921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23722710.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 166058921 is about 12886.3851021146. The cubic root of 166058921 is about 549.6514827838.

The spelling of 166058921 in words is "one hundred sixty-six million, fifty-eight thousand, nine hundred twenty-one".