diff --git a/src/PhpSpreadsheet/Cell/DefaultValueBinder.php b/src/PhpSpreadsheet/Cell/DefaultValueBinder.php
index 0e6433a4..cd05cf8b 100644
--- a/src/PhpSpreadsheet/Cell/DefaultValueBinder.php
+++ b/src/PhpSpreadsheet/Cell/DefaultValueBinder.php
@@ -51,16 +51,16 @@ class DefaultValueBinder implements IValueBinder
         // Match the value against a few data types
         if ($pValue === null) {
             return DataType::TYPE_NULL;
+        } elseif (is_float($pValue) || is_int($pValue)) {
+            return DataType::TYPE_NUMERIC;
+        } elseif (is_bool($pValue)) {
+            return DataType::TYPE_BOOL;
         } elseif ($pValue === '') {
             return DataType::TYPE_STRING;
         } elseif ($pValue instanceof RichText) {
             return DataType::TYPE_INLINE;
-        } elseif ($pValue[0] === '=' && strlen($pValue) > 1) {
+        } elseif (is_string($pValue) && $pValue[0] === '=' && strlen($pValue) > 1) {
             return DataType::TYPE_FORMULA;
-        } elseif (is_bool($pValue)) {
-            return DataType::TYPE_BOOL;
-        } elseif (is_float($pValue) || is_int($pValue)) {
-            return DataType::TYPE_NUMERIC;
         } elseif (preg_match('/^[\+\-]?(\d+\\.?\d*|\d*\\.?\d+)([Ee][\-\+]?[0-2]?\d{1,3})?$/', $pValue)) {
             $tValue = ltrim($pValue, '+-');
             if (is_string($pValue) && $tValue[0] === '0' && strlen($tValue) > 1 && $tValue[1] !== '.') {