You can use command "httpd -V". httpd should be present in the bin folder of Apache.
# /usr/local/apache/bin/httpd -VServer version: Apache/2.4.29 (Unix)Server built: Feb 14 2018 13:01:48Server's Module Magic Number: 20120211:68Server loaded: APR 1.6.2, APR-UTIL 1.6.0Compiled using: APR 1.6.2, APR-UTIL 1.6.0Architecture: 64-bitServer MPM: event threaded: yes (fixed thread count) forked: yes (variable process count)
# /usr/local/apache/bin/httpd -V
Server version: Apache/2.4.29 (Unix)
Server built: Feb 14 2018 13:01:48
Server's Module Magic Number: 20120211:68
Server loaded: APR 1.6.2, APR-UTIL 1.6.0
Compiled using: APR 1.6.2, APR-UTIL 1.6.0
Architecture: 64-bit
Server MPM: event
threaded: yes (fixed thread count)
forked: yes (variable process count)