diff --git a/xlsxwriter.class.php b/xlsxwriter.class.php
index 81bc7589d..cc8c15112 100644
--- a/xlsxwriter.class.php
+++ b/xlsxwriter.class.php
@@ -369,7 +369,11 @@ protected function writeCell(XLSXWriter_BuffererWriter &$file, $row_number, $col
 		} elseif ($num_format_type=='n_datetime') {
 			$file->write('<c r="'.$cell_name.'" s="'.$cell_style_idx.'" t="n"><v>'.self::convert_date_time($value).'</v></c>');
 		} elseif ($num_format_type=='n_numeric') {
-			$file->write('<c r="'.$cell_name.'" s="'.$cell_style_idx.'" t="n"><v>'.self::xmlspecialchars($value).'</v></c>');//int,float,currency
+			if (!is_string($value) || $value=='0' || ($value[0]!='0' && ctype_digit($value)) || preg_match("/^\-?(0|[1-9][0-9]*)?(\.[0-9]+)?$/", $value)){
+				$file->write('<c r="'.$cell_name.'" s="'.$cell_style_idx.'" t="n"><v>'.self::xmlspecialchars($value).'</v></c>');//int,float,currency
+			} else { //not numeric, treat it as string
+				$file->write('<c r="'.$cell_name.'" s="'.$cell_style_idx.'" t="inlineStr"><is><t>'.self::xmlspecialchars($value).'</t></is></c>');
+			}
 		} elseif ($num_format_type=='n_string') {
 			$file->write('<c r="'.$cell_name.'" s="'.$cell_style_idx.'" t="inlineStr"><is><t>'.self::xmlspecialchars($value).'</t></is></c>');
 		} elseif ($num_format_type=='n_auto' || 1) { //auto-detect unknown column types