[angularjs] validate natural input number with ngpattern

I use ng-pattern="/0-9/" to set price_field do not accept decimal number. But when I input natural number (from 0 to 9999999),ng-show gets activated with Not valid number!.

Where did I go wrong?. Please help.

<form name="myform" data-ng-submit="create()">
        <input type="number"
               name="price_field"
               data-ng-model="price"
               require
               ng-pattern="/0-9/">
        <span  ng-show="myform.price_field.$error.pattern">Not valid number!</span>
        <input type="submit" class="btn">
</form>

This is working

<form name="myform" ng-submit="create()">
    <input type="number"
           name="price_field"
           ng-model="price"
           require
           ng-pattern="/^\d{0,9}(\.\d{1,9})?$/">
    <span  ng-show="myform.price_field.$error.pattern">Not valid number!</span>
    <input type="submit" class="btn">
 </form>

<label>Mobile Number(*)</label>
<input id="txtMobile" ng-maxlength="10" maxlength="10" Validate-phone  required  name='strMobileNo' ng-model="formModel.strMobileNo" type="text"  placeholder="Enter Mobile Number">
<span style="color:red" ng-show="regForm.strMobileNo.$dirty && regForm.strMobileNo.$invalid"><span ng-show="regForm.strMobileNo.$error.required">Phone is required.</span>

the following code will help for phone number validation and the respected directive is

app.directive('validatePhone', function() {
var PHONE_REGEXP = /^[789]\d{9}$/;
  return {
    link: function(scope, elm) {
      elm.on("keyup",function(){
            var isMatchRegex = PHONE_REGEXP.test(elm.val());
            if( isMatchRegex&& elm.hasClass('warning') || elm.val() == ''){
              elm.removeClass('warning');
            }else if(isMatchRegex == false && !elm.hasClass('warning')){
              elm.addClass('warning');
            }
      });
    }
  }
});