/usr/lib/libglibmm-utils.so is in libglibmm-utils-dev 0.4.1-0ubuntu2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/libglibmm-utils.so.2.0.0
/usr/lib/libglibmm-utils.so.2.0.0