581840 has 40 divisors (see below), whose sum is σ = 1547520. Its totient is φ = 199296.

The previous prime is 581821. The next prime is 581843. The reversal of 581840 is 48185.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (581843) by changing a digit.

581840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41 + ... + 1079.

It is an arithmetic number, because the mean of its divisors is an integer number (38688).

2⁵⁸¹⁸⁴⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 581840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (773760).

581840 is an abundant number, since it is smaller than the sum of its proper divisors (965680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

581840 is a wasteful number, since it uses less digits than its factorization.

581840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059 (or 1053 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 26.

The square root of 581840 is about 762.7843732012. The cubic root of 581840 is about 83.4836044159.

The spelling of 581840 in words is "five hundred eighty-one thousand, eight hundred forty".