diff --git a/docs/src/rust/lib/primes.rst b/docs/src/rust/lib/primes.rst
index ac691bce..2d85dcd2 100644
--- a/docs/src/rust/lib/primes.rst
+++ b/docs/src/rust/lib/primes.rst
@@ -58,10 +58,6 @@ Includes
 
   .. rust:fn:: pub fn primes::PrimeFactors::next() -> Option<I> where I: Hash + Zero + One + Add + Ord + Copy + Div<Output=I> + Rem<Output=I>
 
-.. rust:fn:: pub fn primes::proper_divisors<I>(x: I) -> Vec<I> where I: NumAssign + Bounded + Ord + Eq + Hash + Copy
-
-  This function returns a vector of the proper divisors of a number.
-
 .. rust:fn:: pub fn is_composite<I>(x: I) -> I where I: Hash + Zero + One + Add + Ord + Copy + Div<Output=I> + Rem<Output=I>
 
   Returns ``0`` if the number is prime, and the smallest prime factor otherwise.
diff --git a/rust/src/include/primes.rs b/rust/src/include/primes.rs
index a70d5882..e921dd82 100644
--- a/rust/src/include/primes.rs
+++ b/rust/src/include/primes.rs
@@ -130,22 +130,6 @@ pub fn prime_factors<I>(x: I) -> PrimeFactors<I>
     return PrimeFactors::new(x);
 }
 
-pub fn proper_divisors<I>(x: I) -> Vec<I>
-where I: Hash + Zero + One + Add + Ord + Copy + Div<Output=I> + Rem<Output=I>
-{
-    let mut ret: Vec<I> = vec![];
-    let factors: Vec<I> = PrimeFactors::new(x).collect();
-    ret.extend(factors.clone());
-    for i in 2..(factors.len()) {
-        for v in factors.iter().combinations(i) {
-            ret.push(v.into_iter().fold(one(), |x, y| x * (*y)));
-        }
-    }
-    ret.sort();
-    ret.dedup();
-    return ret;
-}
-
 pub fn is_composite<I>(x: I) -> I
 where I: Hash + Zero + One + Add + Ord + Copy + Div<Output=I> + Rem<Output=I>
 {