Accessing node data in vis.js click handler

I have a network graph of nodes and edges and would like to get the node data once it gets clicked. e.g,

var network = new vis.Network(container, data, options);
network.on( 'click', function(properties) {
    console.log('clicked node ' + properties.nodes);
});

But this just returns some internal id [105]. Is there a way to get the actual data that is associated with the node?