diff --git a/src/wp-includes/post.php b/src/wp-includes/post.php
index bb7e37a9a2..cccc5c0871 100644
--- a/src/wp-includes/post.php
+++ b/src/wp-includes/post.php
@@ -1665,12 +1665,20 @@ function set_post_type( $post_id = 0, $post_type = 'post' ) {
  * For all others, the 'publicly_queryable' value will be used.
  *
  * @since 4.4.0
+ * @since 4.5.0 Added the ability to pass a post type name in addition to object.
  *
- * @param object $post_type_object Post type object.
+ * @param object $post_type Post type name or object.
  * @return bool Whether the post type should be considered viewable.
  */
-function is_post_type_viewable( $post_type_object ) {
-	return $post_type_object->publicly_queryable || ( $post_type_object->_builtin && $post_type_object->public );
+function is_post_type_viewable( $post_type ) {
+	if ( is_scalar( $post_type ) ) {
+		$post_type = get_post_type_object( $post_type );
+		if ( ! $post_type ) {
+			return false;
+		}
+	}
+
+	return $post_type->publicly_queryable || ( $post_type->_builtin && $post_type->public );
 }
 
 /**
diff --git a/tests/phpunit/tests/post/isPostTypeViewable.php b/tests/phpunit/tests/post/isPostTypeViewable.php
index 17b3f7de7b..2a3956bbc1 100644
--- a/tests/phpunit/tests/post/isPostTypeViewable.php
+++ b/tests/phpunit/tests/post/isPostTypeViewable.php
@@ -71,4 +71,24 @@ class Tests_Post_IsPostTypeViewable extends WP_UnitTestCase {
 		$page = get_post_type_object( 'page' );
 		$this->assertTrue( is_post_type_viewable( $page ) );
 	}
+
+	/**
+	 * @ticket 35609
+	 */
+	public function test_should_accept_post_type_name() {
+		register_post_type( 'wptests_pt', array(
+			'publicly_queryable' => true,
+			'_builtin' => false,
+			'public' => false,
+		) );
+
+		$this->assertTrue( is_post_type_viewable( 'wptests_pt' ) );
+	}
+
+	/**
+	 * @ticket 35609
+	 */
+	public function test_should_return_false_for_bad_post_type_name() {
+		$this->assertFalse( is_post_type_viewable( 'foo' ) );
+	}
 }