centos6 - Apache want port 80 without binding it to this port

When I want to start my apache server, it shows me this error:

Starting httpd:

(98) Address already in use: make_sock: could not bind to address [::]:80

(98) Address already in use: make_sock: could not bind to address 0.0.0.0:80

no listening sockets available, shutting
down Unable to open logs

[FAILED]

My httpd.conf file:

Listen 8181

As you can see, I have deleted everything else. Still, Apache wants to bind to port 80 which is used by varnish. Any idea how to solve it?