43581 has 8 divisors (see below), whose sum is σ = 59200. Its totient is φ = 28512.

The previous prime is 43579. The next prime is 43591. The reversal of 43581 is 18534.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 43581 - 2¹ = 43579 is a prime.

It is a super-2 number, since 2×43581² = 3798607122, 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 (43541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120 + ... + 318.

It is an arithmetic number, because the mean of its divisors is an integer number (7400).

2⁴³⁵⁸¹ is an apocalyptic number.

It is an amenable number.

43581 is a deficient number, since it is larger than the sum of its proper divisors (15619).

43581 is a wasteful number, since it uses less digits than its factorization.

43581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275.

The product of its digits is 480, while the sum is 21.

The square root of 43581 is about 208.7606284719. The cubic root of 43581 is about 35.1910639334.

The spelling of 43581 in words is "forty-three thousand, five hundred eighty-one".