166397645 has 4 divisors (see below), whose sum is σ = 199677180. Its totient is φ = 133118112.

The previous prime is 166397629. The next prime is 166397657. The reversal of 166397645 is 546793661.

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 35844169 + 130553476 = 5987^2 + 11426^2 .

It is a cyclic number.

It is not a de Polignac number, because 166397645 - 2⁴ = 166397629 is a prime.

It is a super-3 number, since 3×166397645³ (a number of 26 digits) contains 333 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 166397645.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16639760 + ... + 16639769.

It is an arithmetic number, because the mean of its divisors is an integer number (49919295).

Almost surely, 2^166397645 is an apocalyptic number.

It is an amenable number.

166397645 is a deficient number, since it is larger than the sum of its proper divisors (33279535).

166397645 is an equidigital number, since it uses as much as digits as its factorization.

166397645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33279534.

The product of its digits is 816480, while the sum is 47.

The square root of 166397645 is about 12899.5211151422. The cubic root of 166397645 is about 550.0249520360.

The spelling of 166397645 in words is "one hundred sixty-six million, three hundred ninety-seven thousand, six hundred forty-five".