Primus

Single latin names which perhaps seem insignificant.

Quartus – Romans 16:23
Meaning – Fourth
Epithet - ‘a brother’
That’s encouraging to know that the apostle Paul found him to be a brother. That is high praise indeed.
And though unworthy children we may be, the Lord Jesus is not ashamed to call us brothers - Hebrews 2:11

Tertius – Romans 16:22
Meaning – Third
The scribe/amanuensis of Paul.
What a privilege this man had; he was used to write the original words of the apostle Paul who of course was governed by the Spirit of God. But what Tertius must have enjoyed at the feet of the Apostle Paul while he dictated what to write, all the arguments, the nation of Israel and the practical application of faith in Christ.

Secundus – Acts 20:4
Meaning – second
Epithet - a companion
Accompanied Paul on his third journey. What a privilege that would have been, to accompany Paul and been his companion and break bread with him in Troas.

As pointed out the name Quartus means Four, Teritus means Three, Secundus menas Two. However, there is only One Primus – The Lord Jesus Himself. No one can take His place; He is the First and the Last. Jesus takes the highest station; O what joy the sight affords! Crown Him! Crown Him! King of kings and Lord of lords.