diff --git a/ext/standard/math.c b/ext/standard/math.c
index ad2823ea49bf6..341b84396447b 100644
--- a/ext/standard/math.c
+++ b/ext/standard/math.c
@@ -1136,6 +1136,7 @@ PHP_FUNCTION(number_format)
 {
 	double num;
 	zend_long dec = 0;
+	int dec_int;
 	char *thousand_sep = NULL, *dec_point = NULL;
 	size_t thousand_sep_len = 0, dec_point_len = 0;
 
@@ -1156,7 +1157,13 @@ PHP_FUNCTION(number_format)
 		thousand_sep_len = 1;
 	}
 
-	RETURN_STR(_php_math_number_format_ex(num, (int)dec, dec_point, dec_point_len, thousand_sep, thousand_sep_len));
+	if (dec >= 0) {
+		dec_int = ZEND_LONG_INT_OVFL(dec) ? INT_MAX : (int)dec;
+	} else {
+		dec_int = ZEND_LONG_INT_UDFL(dec) ? INT_MIN : (int)dec;
+	}
+
+	RETURN_STR(_php_math_number_format_ex(num, dec_int, dec_point, dec_point_len, thousand_sep, thousand_sep_len));
 }
 /* }}} */