How to preserve data types during ImportDataTable in C#, VB.NET?

//Importing a DataTable to Worksheet
worksheet.ImportDataTable(dt, true, 1, 1, -1, -1, true);

using System;
using System.Data;
using System.IO;
using Syncfusion.XlsIO;
 
namespace PreserveLongNumber
{
    class Program
    {
            static void Main(string[] args)
 {
     using (ExcelEngine excelEngine = new ExcelEngine())
     {
  IApplication application = excelEngine.Excel;
  application.DefaultVersion = ExcelVersion.Excel2013;
 
  //Create new workbook
  IWorkbook workbook = application.Workbooks.Create(1);
 
  //Accessing first worksheet in the workbook
  IWorksheet worksheet = workbook.Worksheets[0];
 
  //Creating a DataTable to import
  DataTable dt = new DataTable();
  dt.Columns.Add("Name", typeof(string));
  dt.Columns.Add("Number", typeof(long));
  dt.Columns.Add("StringNumber", typeof(string));
  dt.Columns.Add("StringDate", typeof(string));
  dt.Columns.Add("Date", typeof(DateTime));
 
  DataRow dr1 = dt.NewRow();
  dr1["Name"] = "aaa";
  dr1["Number"] = 6755510089231745873;
  dr1["StringNumber"] = "6755510089231745873";
  dr1["Date"] = DateTime.Now.ToString();
  dr1["StringDate"] = DateTime.Now.ToString();
  dt.Rows.Add(dr1);
 
  DataRow dr2 = dt.NewRow();
  dr2["Name"] = "bbb";
  dr2["Number"] = 6755510089231745873;
  dr2["StringNumber"] = "6755510089231745873";
  dr2["Date"] = DateTime.Now.ToString();
  dr2["StringDate"] = DateTime.Now.ToString();
  dt.Rows.Add(dr2);
 
  DataRow dr3 = dt.NewRow();
  dr3["Name"] = "ccc";
  dr3["Number"] = 6755510089231745873;
  dr3["StringNumber"] = "6755510089231745873";
  dr3["Date"] = DateTime.Now.ToString();
  dr3["StringDate"] = DateTime.Now.ToString();
  dt.Rows.Add(dr3);
 
  //Importing a DataTable to Worksheet
  worksheet.ImportDataTable(dt, true, 1, 1, -1, -1, true);
 
  //Save the workbook as stream
  Stream stream = File.Create("Output.xlsx");
  workbook.SaveAs(stream);
     }
           }
     }
}

Imports Syncfusion.XlsIO
Imports System
Imports System.Data
Imports System.IO
 
Namespace PreserveLongNumber
    Class Program
        Private Shared Sub Main(ByVal args() As String)
 Using excelEngine As ExcelEngine = New ExcelEngine
  Dim application As IApplication = excelEngine.Excel
  application.DefaultVersion = ExcelVersion.Excel2013
 
  'Create new workbook
  Dim workbook As IWorkbook = application.Workbooks.Create(1)
 
  'Accessing first worksheet in the workbook
  Dim worksheet As IWorksheet = workbook.Worksheets(0)
 
  'Creating a DataTable to import
  Dim dt As DataTable = New DataTable
  dt.Columns.Add("Name", GetType(System.String))
  dt.Columns.Add("Number", GetType(System.Int64))
  dt.Columns.Add("StringNumber", GetType(System.String))
  dt.Columns.Add("StringDate", GetType(System.String))
  dt.Columns.Add("Date", GetType(DateTime))
 
  Dim dr1 As DataRow = dt.NewRow
  dr1("Name") = "aaa"
  dr1("StringNumber") = "6755510089231745873"
  dr1("Date") = DateTime.Now.ToString
  dr1("StringDate") = DateTime.Now.ToString
  dt.Rows.Add(dr1)
 
  Dim dr2 As DataRow = dt.NewRow
  dr2("Name") = "bbb"
  dr2("StringNumber") = "6755510089231745873"
  dr2("Date") = DateTime.Now.ToString
  dr2("StringDate") = DateTime.Now.ToString
  dt.Rows.Add(dr2)
 
  Dim dr3 As DataRow = dt.NewRow
  dr3("Name") = "ccc"
  dr3("StringNumber") = "6755510089231745873"
  dr3("Date") = DateTime.Now.ToString
  dr3("StringDate") = DateTime.Now.ToString
  dt.Rows.Add(dr3)
 
  'Importing a DataTable to Worksheet
  worksheet.ImportDataTable(dt, True, 1, 1, -1, -1, True)
 
  'Save the workbook as stream
  Dim stream As Stream = File.Create("Output.xlsx")
  workbook.SaveAs(stream)
 End Using
        End Sub
    End Class
End Namespace