43531 has 4 divisors (see below), whose sum is σ = 44064. Its totient is φ = 43000.

The previous prime is 43517. The next prime is 43541. The reversal of 43531 is 13534.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 43531 - 2⁵ = 43499 is a prime.

It is a super-2 number, since 2×43531² = 3789895922, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (43541) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 115 + ... + 316.

It is an arithmetic number, because the mean of its divisors is an integer number (11016).

2⁴³⁵³¹ is an apocalyptic number.

43531 is a deficient number, since it is larger than the sum of its proper divisors (533).

43531 is a wasteful number, since it uses less digits than its factorization.

43531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532.

The product of its digits is 180, while the sum is 16.

The square root of 43531 is about 208.6408397222. The cubic root of 43531 is about 35.1776006770.

The spelling of 43531 in words is "forty-three thousand, five hundred thirty-one".