I have found the solution below is the code in which you can see the address and XY in the same popup window.
// Set up a locator task using the world geocoding service
var locator = new Locator("https://geocode.arcgis.com/arcgis/rest/services/World/GeocodeServer");
map.on("click", function(evt) {
locator.locationToAddress(evt.mapPoint, 100);
});
locator.on('location-to-address-complete', function(evt) {
console.log(evt);
var location = webMercatorUtils.geographicToWebMercator(evt.address.location)
var screenPoint = map.toScreen(location);
console.log(screenPoint);
// dig out the best attribute from matched address to display in popup
map.infoWindow.setTitle("Coordinates/Address");
map.infoWindow.setContent("Latitude: " + evt.address.location.x.toFixed(3) + "<br>Longitude: " + evt.address.location.y.toFixed(3) + "<br> Address: " + evt.address.address.LongLabel);
map.infoWindow.show(screenPoint);
// add an if/else and use the map click xy that you saved from the other event listener if no address was found
})