They are called "minor" not because they are unimportant, but because their books are shorter than the "major" prophets: Isaiah, Jeremiah, and Ezekiel, and sometimes Daniel.
The twelve disciples of our Lord Jesus, whom he also named apostles: See Luke 6:12-16.
Note: Acts 1:15-25 tells how, after Judas Iscariot had committed
suicide and our Lord had ascended into heaven, Matthias was chosen to replace
Judas,
"and he was numbered with the eleven apostles."