You can use the IQrouter Administrative Interface to change the system password. Simply login with your existing password and then select the Configure-->System menu option. Enter your new password and select the "Save & Apply" button. Please make note of this password, as it will be required to log back into the router's administrative interface to adjust settings or look at status.
See the FAQ, What can I do if I forgot my IQrouter password?, If you forget your password.