Pure CSS to “float” to the right the number of children of an admin_bar child node

Putting a padding-right on the text title that is around the same as width of your absolute number, would prevent the overlap.

#wpadminbar #wp-admin-bar-my-admin-bar-node-default > li > .ab-item {
    padding-right: 45px;
}

or you could wrap your title in a span as well, make them both blocks, and then do a display:flex; on the parent and use flex to size and position.