581161 has 4 divisors (see below), whose sum is σ = 664192. Its totient is φ = 498132.

The previous prime is 581149. The next prime is 581171. The reversal of 581161 is 161185.

581161 is digitally balanced in base 2, 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, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 161185 = 5 ⋅32237.

It is a cyclic number.

It is not a de Polignac number, because 581161 - 2¹¹ = 579113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (581101) 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, 41505 + ... + 41518.

It is an arithmetic number, because the mean of its divisors is an integer number (166048).

2⁵⁸¹¹⁶¹ is an apocalyptic number.

It is an amenable number.

581161 is a deficient number, since it is larger than the sum of its proper divisors (83031).

581161 is an equidigital number, since it uses as much as digits as its factorization.

581161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83030.

The product of its digits is 240, while the sum is 22.

The square root of 581161 is about 762.3391633650. The cubic root of 581161 is about 83.4511170012.

The spelling of 581161 in words is "five hundred eighty-one thousand, one hundred sixty-one".