8721173 has 4 divisors (see below), whose sum is σ = 8811180. Its totient is φ = 8631168.

The previous prime is 8721157. The next prime is 8721191. The reversal of 8721173 is 3711278.

8721173 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 2380849 + 6340324 = 1543^2 + 2518^2 .

It is a cyclic number.

It is not a de Polignac number, because 8721173 - 2⁴ = 8721157 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 (8721473) 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, 44858 + ... + 45051.

It is an arithmetic number, because the mean of its divisors is an integer number (2202795).

Almost surely, 2^8721173 is an apocalyptic number.

It is an amenable number.

8721173 is a deficient number, since it is larger than the sum of its proper divisors (90007).

8721173 is an equidigital number, since it uses as much as digits as its factorization.

8721173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90006.

The product of its digits is 2352, while the sum is 29.

The square root of 8721173 is about 2953.1632193294. The cubic root of 8721173 is about 205.8377221368.

The spelling of 8721173 in words is "eight million, seven hundred twenty-one thousand, one hundred seventy-three".