166397089 has 4 divisors (see below), whose sum is σ = 166439700. Its totient is φ = 166354480.

The previous prime is 166397069. The next prime is 166397093. The reversal of 166397089 is 980793661.

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

It can be written as a sum of positive squares in 2 ways, for example, as 74390625 + 92006464 = 8625^2 + 9592^2 .

It is a cyclic number.

It is not a de Polignac number, because 166397089 - 2⁷ = 166396961 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166397059) 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, 14782 + ... + 23479.

It is an arithmetic number, because the mean of its divisors is an integer number (41609925).

Almost surely, 2^166397089 is an apocalyptic number.

It is an amenable number.

166397089 is a deficient number, since it is larger than the sum of its proper divisors (42611).

166397089 is an equidigital number, since it uses as much as digits as its factorization.

166397089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42610.

The product of its (nonzero) digits is 489888, while the sum is 49.

The square root of 166397089 is about 12899.4995639366. The cubic root of 166397089 is about 550.0243394187.

The spelling of 166397089 in words is "one hundred sixty-six million, three hundred ninety-seven thousand, eighty-nine".