Namesakes
Bishops of Rome and the Popes:
3 popes, 1 antipope
Callixtus I (a.k.a. Calixtus) 217-222 
Callixtus II (a.k.a. Calixtus) 1119-1124
Callixtus (a.k.a. Calixtus) 1168-1178
Callixtus III (a.k.a. Calixtus) 1455-1458
Saints:
1 blessed, 1 saint
Saint Callixtus I (a.k.a. Calixtus) ?-222
Blessed Calixtus Caravario ?-1930