Each Prophet will gather their Ummah up after we are resurrected back into our physical and human states for Judgement day.
I am among the Ummah of the Prophet Muhammad.
He is the greatest Prophet and will have the highest position in all of Jannah.
In fact, out of all the Prophets, they will be impressed by Muhammad's Ummah. On Judgement Day or after it, i'm not sure, we will all gather up into our Ummahs for our Prophets who guided us.
There they will be amazed. The other Prophets will be intrigued by us.
We will be the Ummah to enter first into Jannah.
Truly I can say that the Prophet Muhammad, pbuh, is the greatest Prophet and is the only Prophet for all of mankind.
May Allah grant us all Jannah and may he gather us all with Prophet Muhammad, pbuh.