diff --git a/src/PhpSpreadsheet/Calculation/Calculation.php b/src/PhpSpreadsheet/Calculation/Calculation.php
index 93d7058d..923b19e9 100644
--- a/src/PhpSpreadsheet/Calculation/Calculation.php
+++ b/src/PhpSpreadsheet/Calculation/Calculation.php
@@ -3658,8 +3658,8 @@ class Calculation
                             $rangeWS2 = $rangeWS1;
                         }
                         $refSheet = $pCellParent;
-                        if ($rangeSheetRef !== $pCellParent->getTitle()) {
-                            $refSheet = $pCell->getWorksheet()->getParent()->getSheetByName($rangeSheetRef);
+                        if ($pCellParent !== null && $rangeSheetRef !== $pCellParent->getTitle()) {
+                            $refSheet = $pCellParent->getParent()->getSheetByName($rangeSheetRef);
                         }
                         if ((is_int($startRowColRef)) && (ctype_digit($val)) &&
                             ($startRowColRef <= 1048576) && ($val <= 1048576)) {
diff --git a/src/PhpSpreadsheet/Calculation/TextData.php b/src/PhpSpreadsheet/Calculation/TextData.php
index ea00ef1c..bbb03926 100644
--- a/src/PhpSpreadsheet/Calculation/TextData.php
+++ b/src/PhpSpreadsheet/Calculation/TextData.php
@@ -266,7 +266,7 @@ class TextData
         if (!is_numeric($value) || !is_numeric($decimals)) {
             return Functions::NAN();
         }
-        $decimals = floor($decimals);
+        $decimals = (int) floor($decimals);
 
         $valueResult = round($value, $decimals);
         if ($decimals < 0) {