"package-cleanup —quiet —leaves from the yum-utils package will list the library packages..."

package-cleanup —quiet —leaves from the yum-utils package will list the library packages which aren’t relied upon by other packages. Unfortunately it tends to be a bit overeager. On my system, for example, it suggested removing libvirt. Adding the —exclude-bin argument helps. If you’re happy with it’s suggestion, then to clean up the packages, do:

# package-cleanup —quiet —leaves —exclude-bin | xargs yum remove -y