16661173 has 4 divisors (see below), whose sum is σ = 17641260. Its totient is φ = 15681088.

The previous prime is 16661147. The next prime is 16661213. The reversal of 16661173 is 37116661.

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 7279204 + 9381969 = 2698^2 + 3063^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16661173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16661123) 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, 490018 + ... + 490051.

It is an arithmetic number, because the mean of its divisors is an integer number (4410315).

Almost surely, 2^16661173 is an apocalyptic number.

It is an amenable number.

16661173 is a deficient number, since it is larger than the sum of its proper divisors (980087).

16661173 is an equidigital number, since it uses as much as digits as its factorization.

16661173 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980086.

The product of its digits is 4536, while the sum is 31.

The square root of 16661173 is about 4081.8100151771. The cubic root of 16661173 is about 255.4084087231.

The spelling of 16661173 in words is "sixteen million, six hundred sixty-one thousand, one hundred seventy-three".