diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 97d1164..e124000 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -12,7 +12,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Build
         run: cargo build --verbose
       - name: Check formatting
diff --git a/src/lib.rs b/src/lib.rs
index d45000f..d3a85e8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -247,7 +247,7 @@ impl Personnummer {
 
     /// Check if the person holding the personal identity number is a female.
     pub fn is_female(&self) -> bool {
-        (self.serial % 10) % 2 == 0
+        (self.serial % 10).is_multiple_of(2)
     }
 
     /// Check if the person holding the personal identity number is a male.