diff --git a/exercises/practice/perfect-numbers/.meta/tests.toml b/exercises/practice/perfect-numbers/.meta/tests.toml
index ec288891..81d48408 100644
--- a/exercises/practice/perfect-numbers/.meta/tests.toml
+++ b/exercises/practice/perfect-numbers/.meta/tests.toml
@@ -27,6 +27,9 @@ description = "Abundant numbers -> Medium abundant number is classified correctl
 [ec7792e6-8786-449c-b005-ce6dd89a772b]
 description = "Abundant numbers -> Large abundant number is classified correctly"
 
+[05f15b93-849c-45e9-9c7d-1ea131ef7d10]
+description = "Abundant numbers -> Perfect square abundant number is classified correctly"
+
 [e610fdc7-2b6e-43c3-a51c-b70fb37413ba]
 description = "Deficient numbers -> Smallest prime deficient number is classified correctly"
 
diff --git a/exercises/practice/perfect-numbers/test.sml b/exercises/practice/perfect-numbers/test.sml
index 89602e58..7c897d37 100644
--- a/exercises/practice/perfect-numbers/test.sml
+++ b/exercises/practice/perfect-numbers/test.sml
@@ -27,7 +27,10 @@ val testsuite =
         (fn _ => classify 30 |> Expect.equalTo (SOME Abundant)),
 
       test "Large abundant number is classified correctly"
-        (fn _ => classify 33550335 |> Expect.equalTo (SOME Abundant))
+        (fn _ => classify 33550335 |> Expect.equalTo (SOME Abundant)),
+
+      test "Perfect square abundant number is classified correctly"
+        (fn _ => classify 196 |> Expect.equalTo (SOME Abundant))
     ],
 
     describe "Deficient numbers" [
@@ -48,10 +51,10 @@ val testsuite =
     ],
 
     describe "Invalid inputs" [
-      test "Zero is rejected (not a natural number)"
+      test "Zero is rejected (as it is not a positive integer)"
         (fn _ => classify 0 |> Expect.equalTo NONE),
 
-      test "Negative integer is rejected (not a natural number)"
+      test "Negative integer is rejected (as it is not a positive integer)"
         (fn _ => classify ~1 |> Expect.equalTo NONE)
     ]
   ]