using System;
using System.Globalization;
public class Example
{
public static void Main()
{
double value = 123456.125E21;
Console.WriteLine(value.ToString(CultureInfo.InvariantCulture));
Console.WriteLine(value.ToString(CultureInfo.CreateSpecificCulture("en-GB")));
Console.WriteLine(value.ToString(CultureInfo.CreateSpecificCulture("de-DE")));
}
}
/*
1.23456125E+26
1.23456125E+26
1,23456125E+26
*/