diff --git a/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldInt.php b/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldInt.php
--- a/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldInt.php
+++ b/src/infrastructure/customfield/standard/PhabricatorStandardCustomFieldInt.php
@@ -11,7 +11,7 @@
     $indexes = array();
 
     $value = $this->getFieldValue();
-    if (strlen($value)) {
+    if (is_int($value) && $value !== null) {
       $indexes[] = $this->newNumericIndex((int)$value);
     }
 
@@ -53,7 +53,7 @@
     PhabricatorCursorPagedPolicyAwareQuery $query,
     $value) {
 
-    if (strlen($value)) {
+    if (is_int($value) && $value !== null) {
       $query->withApplicationSearchContainsConstraint(
         $this->newNumericIndex(null),
         $value);
@@ -84,7 +84,7 @@
 
     foreach ($xactions as $xaction) {
       $value = $xaction->getNewValue();
-      if (strlen($value)) {
+      if (is_int($value) && $value !== null) {
         if (!preg_match('/^-?\d+/', $value)) {
           $errors[] = new PhabricatorApplicationTransactionValidationError(
             $type,
@@ -104,9 +104,9 @@
 
     $old = $xaction->getOldValue();
     $new = $xaction->getNewValue();
-    if (!strlen($old) && strlen($new)) {
+    if (!phutil_nonempty_scalar($old) && phutil_nonempty_scalar($new)) {
       return true;
-    } else if (strlen($old) && !strlen($new)) {
+    } else if (phutil_nonempty_scalar($old) && !phutil_nonempty_scalar($new)) {
       return true;
     } else {
       return ((int)$old !== (int)$new);