An IRA can be invested in an annuity, in which case it's an IRA annuity. However, if it's an IRA (IRA/SEP/SIMPLE box marked), the distribution is governed by IRA rules, not by annuity rules. If box 7 has code 4 and the IRA/SEP/SIMPLE box is marked, it's an IRA (and it doesn't matter if the IRA is invested in an annuity or not).