Cannot start httpd on CentOS - apache

Question

I cannot restart apache on CentOS. The results are below. I cannot locate a meaningful error to fix the issue.
Running service httpd start
Results in
Job for httpd.service failed because the control process exited with error code. See "systemctl status httpd.service" and "journalctl -xe" for details.
Then running systemctl status httpd.service
Results in
httpd.service - The Apache HTTP Server
Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Sun 2017-06-11 08:29:11 EDT; 15min ago
Docs: man:httpd(8)
man:apachectl(8)
Process: 640 ExecStop=/bin/kill -WINCH ${MAINPID} (code=exited, status=1/FAILURE)
Process: 638 ExecStart=/usr/sbin/httpd $OPTIONS -DFOREGROUND (code=killed, signal=SEGV)
Main PID: 638 (code=killed, signal=SEGV)
Jun 11 08:29:11 server systemd[1]: Starting The Apache HTTP Server...
Jun 11 08:29:11 server systemd[1]: httpd.service: main process exited, code=killed, status=11/SEGV
Jun 11 08:29:11 server kill[640]: kill: cannot find process ""
Jun 11 08:29:11 server systemd[1]: httpd.service: control process exited, code=exited status=1
Jun 11 08:29:11 server systemd[1]: Failed to start The Apache HTTP Server.
Jun 11 08:29:11 server systemd[1]: Unit httpd.service entered failed state.
Jun 11 08:29:11 server systemd[1]: httpd.service failed.
And journalctl -xe
Results in
Jun 11 08:45:10 server systemd[1]: Starting The Apache HTTP Server...
-- Subject: Unit httpd.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit httpd.service has begun starting up.
Jun 11 08:45:10 server systemd[1]: httpd.service: main process exited, code=killed, status=11/SEGV
Jun 11 08:45:10 server kill[691]: kill: cannot find process ""
Jun 11 08:45:10 server systemd[1]: httpd.service: control process exited, code=exited status=1
Jun 11 08:45:10 server systemd[1]: Failed to start The Apache HTTP Server.
-- Subject: Unit httpd.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit httpd.service has failed.
--
-- The result is failed.
Jun 11 08:45:10 server systemd[1]: Unit httpd.service entered failed state.
Jun 11 08:45:10 server systemd[1]: httpd.service failed.
And from /etc/httpd/logs/error_log
[Sun Jun 11 08:49:33.214825 2017] [suexec:notice] [pid 761] AH01232: suEXEC mechanism enabled (wrapper: /usr/sbin/suexec)
[Sun Jun 11 08:49:33.237392 2017] [auth_digest:notice] [pid 761] AH01757: generating secret for digest authentication ...
[Sun Jun 11 08:49:33.238036 2017] [lbmethod_heartbeat:notice] [pid 761] AH02282: No slotmem from mod_heartmonitor
PHP Fatal error: PHP Startup: apc_shm_create: shmget(0, 67108864, 914) failed: Invalid argument. It is possible that the chosen SHM segment size is higher than the operation system allows. Linux has usually a default limit of 32MB per segment. in Unknown on line 0
PHP Fatal error: PHP Startup: apc_shm_attach: shmat failed: in Unknown on line 0