Converting json to date fromat in jqgrid MVC

Question

/Date(1586240191913)/

I am getting an above as output of date and i want to convert it into following format(dd/mm/yyyy hh/mm/ss)

$grid = $("#jqGrid").jqGrid({
                        url: '/Home/GetData?name=' + name,
                        data: { name: $("#name").val() },
                        mtype: 'GET',
                        datatype: 'json',
                        colModel: [
                            { label: 'name', name: 'name', search: true },
                            { label: 'HireDate', name: 'HireDate', formatter: "date", formatoptions: { newformat: "d/m/Y" }},
                        ],
                        loadonce: true,
                        pager: '#jqGridPager',
                        rowNum: 10,
                        rowList: [10, 20, 30],
                        width: 1080,
                        onSelectRow: function (id) {
                            if (id && id !== lastSel) {
                                jQuery("#jqGrid").saveRow(lastSel, true, 'clientArray');
                                jQuery("#jqGrid").editRow(id, true);
                                lastSel = id;
                            }
                        }
                    });