diff --git a/lib/extract/extractText.js b/lib/extract/extractText.js
index 7a44f2ed..a04eda5a 100644
--- a/lib/extract/extractText.js
+++ b/lib/extract/extractText.js
@@ -8,9 +8,12 @@ const fontFamilySuffix = /[\s"']*$/;
 let cachedFontObjectsFromString = {};
 
 function childrenAsString(children) {
-    if (!children) {
+    if (typeof children === 'undefined') {
         return '';
     }
+    if (typeof children === 'number') {
+        return children.toString();
+    }
     if (typeof children === 'string') {
         return children;
     }