8581321 has 6 divisors (see below), whose sum is σ = 9982410. Its totient is φ = 7355376.

The previous prime is 8581289. The next prime is 8581337. The reversal of 8581321 is 1231858.

8581321 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 7840000 + 741321 = 2800^2 + 861^2 .

It is not a de Polignac number, because 8581321 - 2⁵ = 8581289 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 8581321.

It is not an unprimeable number, because it can be changed into a prime (8581351) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 87516 + ... + 87613.

It is an arithmetic number, because the mean of its divisors is an integer number (1663735).

Almost surely, 2^8581321 is an apocalyptic number.

It is an amenable number.

8581321 is a deficient number, since it is larger than the sum of its proper divisors (1401089).

8581321 is a wasteful number, since it uses less digits than its factorization.

8581321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175143 (or 175136 counting only the distinct ones).

The product of its digits is 1920, while the sum is 28.

The square root of 8581321 is about 2929.3891854788. The cubic root of 8581321 is about 204.7315224273.

It can be divided in two parts, 85 and 81321, that added together give a triangular number (81406 = T₄₀₃).

The spelling of 8581321 in words is "eight million, five hundred eighty-one thousand, three hundred twenty-one".