How many primary apostles followed Jesus?

In Christian theology and ecclesiology, apostles, particularly the Twelve Apostles (also known as the Twelve Disciples or simply the Twelve), were the primary disciples of Jesus according to the New Testament. During the life and ministry of Jesus in the 1st century AD, the apostles were his closest followers and became the primary teachers of the gospel message of Jesus. There is also an Eastern Christian tradition derived from the Gospel of Luke of there having been as many as seventy apostles during the time of Jesus' ministry. The names of the twelve disciples of Jesus are Simon Peter, Andrew, James (the son of Zebedee), John, Philip, Bartholomew, Thomas, Matthew, James (the son of Alphaeus), Thaddaeus, Simon the Zealot and Judas Iscariot.