166128073 has 4 divisors (see below), whose sum is σ = 168231040. Its totient is φ = 164025108.

The previous prime is 166128047. The next prime is 166128091. The reversal of 166128073 is 370821661.

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 a cyclic number.

It is not a de Polignac number, because 166128073 - 2⁹ = 166127561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166128013) 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, 1051365 + ... + 1051522.

It is an arithmetic number, because the mean of its divisors is an integer number (42057760).

Almost surely, 2^166128073 is an apocalyptic number.

It is an amenable number.

166128073 is a deficient number, since it is larger than the sum of its proper divisors (2102967).

166128073 is an equidigital number, since it uses as much as digits as its factorization.

166128073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2102966.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 166128073 is about 12889.0679647521. The cubic root of 166128073 is about 549.7277694099.

The spelling of 166128073 in words is "one hundred sixty-six million, one hundred twenty-eight thousand, seventy-three".