43809 has 8 divisors (see below), whose sum is σ = 61920. Its totient is φ = 27456.

The previous prime is 43801. The next prime is 43853. The reversal of 43809 is 90834.

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

It is not a de Polignac number, because 43809 - 2³ = 43801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (43801) 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 7 ways as a sum of consecutive naturals, for example, 379 + ... + 480.

It is an arithmetic number, because the mean of its divisors is an integer number (7740).

2⁴³⁸⁰⁹ is an apocalyptic number.

It is an amenable number.

43809 is a deficient number, since it is larger than the sum of its proper divisors (18111).

43809 is a wasteful number, since it uses less digits than its factorization.

43809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 43809 is about 209.3059960918. The cubic root of 43809 is about 35.2523261882.

The spelling of 43809 in words is "forty-three thousand, eight hundred nine".