16 teams are taking part in a sports tournament and a draw is about to take place. For simplicity lets say that the teams in each pot are from the same part of the country eg East1, East2, East3, East4 meaning the pots pre draw look like this

[N1, N2, N3, N4] [E1, E2, E3, E4] [S1, S2, S3, S4] [W1, W2, W3, W4]

In the draw a team from each pot will be drawn and placed in a group, so that at the end there will be 4 groups each with 4 teams from different parts of the country

My question is how many different combinations of the entire draw are possible?