Daniel 10:13 But the prince of the kingdom of Persia withstood me [Gabriel] one and twenty days: but, lo, Michael, one of the chief princes, came to help me; and I remained there with the kings of Persia.
Here we see that Gabriel (see Daniel 8:16; 9:21) was withstood 21 days until Michael (Daniel 10:13,21; 12:2) came to help him.
Gabriel is also the angel that gave the message to Zacharias concerning the conception of John the Baptist.
Luke 1:19 And the angel answering said unto him, I am Gabriel, that stand in the presence of God; and am sent to speak unto thee, and to shew thee these glad tidings.
Gabriel also gave the message to Mary concerning the conception of Jesus
Luke 1:26 And in the sixth month the angel Gabriel was sent from God unto a city of Galilee, named Nazareth,
We also see that Michael is an archangel and that it was Michael who contended with the devil over the body of Moses (which God Himself buried in Deut 34:5-6).
Jude 1:9 Yet Michael the archangel, when contending with the devil he disputed about the body of Moses, durst not bring against him a railing accusation, but said, The Lord rebuke thee.
On a side note, in saying “The Lord rebuke thee” Michael follows the same example of Jesus in the account in Zecharia 3:1-2 where Satan is the accuser (Rev 12:10) and Jesus is our advocate (1 John 2:1).
We also see Michael leading his angels in battle against the dragon and his fallen angels.
Rev 12:7 And there was war in heaven: Michael and his angels fought against the dragon; and the dragon fought and his angels,