581081 has 4 divisors (see below), whose sum is σ = 587700. Its totient is φ = 574464.

The previous prime is 581071. The next prime is 581089. The reversal of 581081 is 180185.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 180185 = 5 ⋅36037.

It can be written as a sum of positive squares in 2 ways, for example, as 78400 + 502681 = 280^2 + 709^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-581081 is a prime.

It is a super-2 number, since 2×581081² = 675310257122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (581089) 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, 3176 + ... + 3353.

It is an arithmetic number, because the mean of its divisors is an integer number (146925).

2⁵⁸¹⁰⁸¹ is an apocalyptic number.

It is an amenable number.

581081 is a deficient number, since it is larger than the sum of its proper divisors (6619).

581081 is an equidigital number, since it uses as much as digits as its factorization.

581081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6618.

The product of its (nonzero) digits is 320, while the sum is 23.

The square root of 581081 is about 762.2866914751. The cubic root of 581081 is about 83.4472876575.

The spelling of 581081 in words is "five hundred eighty-one thousand, eighty-one".