Data Calendário Mostrar apenas ícone Clique

<div class="col-md-4 col-sm-4 col-xs-12">
  <label for="datepicker">Date of birth*</label>
  <input type="text" name='datepicker' class="form-control"  value="Select date" id="datepicker" ng-required="true" placeholder="MM/DD/YYYY" >
  <span class="fa fa-calendar"></span>
</div>
Magnificent Mantis