diff --git a/doc/source/whatsnew/v0.21.1.txt b/doc/source/whatsnew/v0.21.1.txt
index 3d4850b334ff9a..e1610937396f4c 100644
--- a/doc/source/whatsnew/v0.21.1.txt
+++ b/doc/source/whatsnew/v0.21.1.txt
@@ -56,6 +56,8 @@ Documentation Changes
 
 Bug Fixes
 ~~~~~~~~~
+- Bug in :meth:`fillna` where maximum recursion depth gets exceeded in comparison (:issue:`18159`).
+
 
 Conversion
 ^^^^^^^^^^
diff --git a/pandas/core/internals.py b/pandas/core/internals.py
index 1d1d71be16c009..45ce847089370e 100644
--- a/pandas/core/internals.py
+++ b/pandas/core/internals.py
@@ -1847,8 +1847,9 @@ def _can_hold_element(self, element):
         if tipo is not None:
             return (issubclass(tipo.type, (np.floating, np.integer)) and
                     not issubclass(tipo.type, (np.datetime64, np.timedelta64)))
-        return (isinstance(element, (float, int, np.floating, np.int_)) and
-                not isinstance(element, (bool, np.bool_, datetime, timedelta,
+        return (
+            isinstance(element, (float, int, np.floating, np.int_, compat.long))
+            and not isinstance(element, (bool, np.bool_, datetime, timedelta,
                                          np.datetime64, np.timedelta64)))
 
     def to_native_types(self, slicer=None, na_rep='', float_format=None,
diff --git a/pandas/tests/internals/test_internals.py b/pandas/tests/internals/test_internals.py
index a22d0174947e13..ac78def824b3e2 100644
--- a/pandas/tests/internals/test_internals.py
+++ b/pandas/tests/internals/test_internals.py
@@ -1222,6 +1222,7 @@ class TestCanHoldElement(object):
     @pytest.mark.parametrize('value, dtype', [
         (1, 'i8'),
         (1.0, 'f8'),
+        (2**63, 'f8'),
         (1j, 'complex128'),
         (True, 'bool'),
         (np.timedelta64(20, 'ns'), '<m8[ns]'),