Following is the working example for updating the totalClicks ngModel.
<html ng-app="ExamplesApp">
<head>
<script src="angular.js"></script>
</head>
<body ng-controller="ExCtrl">
<input type="number" min="0" placeholder="7500" ng-model="totalClicks" required>
<button ng-click="clicks()">Click</button>
<script type="text/javascript">
angular.module('ExamplesApp',[]);
angular.module('ExamplesApp')
.controller('ExCtrl',function($scope){
$scope.totalClicks = '';
$scope.clicks= function(){
alert($scope.totalClicks);
};
});
</script>
</body>
</html>
JSFiddle : http://jsfiddle.net/StT2y/2/