diff --git a/classpath/java/lang/Long.java b/classpath/java/lang/Long.java
index 76366be3ac..e1445ec5d9 100644
--- a/classpath/java/lang/Long.java
+++ b/classpath/java/lang/Long.java
@@ -128,15 +128,19 @@ public final class Long extends Number implements Comparable<Long> {
     int i = 0;
     long number = 0;
     boolean negative = s.startsWith("-");
+    int length = s.length();
     if (negative) {
       i = 1;
+      -- length;
     }
 
+    long factor = pow(radix, length - 1);
     for (; i < s.length(); ++i) {
       char c = s.charAt(i);
       int digit = Character.digit(c, radix);
       if (digit >= 0) {
-        number += digit * pow(radix, (s.length() - i - 1));
+        number += digit * factor;
+        factor /= radix;
       } else {
         throw new NumberFormatException("invalid character " + c + " code " +
                                         (int) c);
diff --git a/test/Misc.java b/test/Misc.java
index 5be739c5d5..be83804e78 100644
--- a/test/Misc.java
+++ b/test/Misc.java
@@ -102,6 +102,10 @@ public class Misc {
       expect(foo > 0);
     }
 
+    expect(Long.parseLong("25214903884") == 25214903884L);
+
+    expect(Long.parseLong("-9223372036854775808") == -9223372036854775808L);
+
     expect(String.valueOf(25214903884L).equals("25214903884"));
 
     expect(String.valueOf(-9223372036854775808L).equals