How to find processes or PID associated with an open PORT?

[root@server1 ~]# lsof -i :80
COMMAND   PID   USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
httpd    1740   root    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20923 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20924 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20925 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20926 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20927 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20928 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20929 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20930 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)
httpd   20931 apache    5u  IPv6  11430      0t0  TCP *:http (LISTEN)

[root@server1 ~]# lsof -i :22
COMMAND   PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
sshd     1129 root    3u  IPv4 609767      0t0  TCP 10.20.30.11:ssh->10.20.30.230:54074 (ESTABLISHED)
sshd     1207 root    3u  IPv4 610131      0t0  TCP 10.20.30.11:ssh->10.20.30.230:54077 (ESTABLISHED)
sshd     1629 root    3u  IPv4  10946      0t0  TCP *:ssh (LISTEN)
sshd     1629 root    4u  IPv6  10948      0t0  TCP *:ssh (LISTEN)
sshd     6352 root    3u  IPv4 621398      0t0  TCP 10.20.30.11:ssh->10.20.30.230:54319 (ESTABLISHED)
ssh      8905 root    3u  IPv4 652131      0t0  TCP 192.168.122.1:41754->client1:ssh (ESTABLISHED)
sshd    21430 root    3r  IPv4 675462      0t0  TCP 10.20.30.11:ssh->10.84.64.173:52323 (ESTABLISHED)
sshd    30917 root    3r  IPv4 754268      0t0  TCP 10.20.30.11:ssh->10.20.30.230:55741 (ESTABLISHED)

[root@server1 ~]# lsof -i :80 -t
1740
20923
20924
20925
20926
20927
20928
20929
20930
20931