Postgres.exe on windows format on command line that starts the process

[bruce@xxxxxxxxxxx]

In Windows PostgreSQL spawns numerous postgres.exe
processes. When you look at the actual command line you see the command
that started the process. For example: "c:/PostgreSQL/8.4/bin/postgres.exe"
"--forkbackend" "1372" 

My questions 
1. In the example above does 1372 represent a port?
2. If it is a port then how can I change the ports used OR avoid using
certain ports? 

Thanks, 
Bruce.