diff --git a/maths/special_numbers/proth_number.py b/maths/special_numbers/proth_number.py
index d330b8d6d..0606e9013 100644
--- a/maths/special_numbers/proth_number.py
+++ b/maths/special_numbers/proth_number.py
@@ -83,8 +83,8 @@ def isprothnumber(number: int) -> bool:
     num = number
     num -= 1
     n = 0
-    while num%2 == 0 :
-        num = num/2
+    while num % 2 == 0:
+        num = num / 2
         n += 1
     return num < (2**n)