string text = "ID для конвертации";
Int32 number;
if(Int32.TryParse(text, out number))
{
String textAsHex = number.ToString("x");
string hex = ("0000000000000000000000000000000000000000000000000000000000000000" + textAsHex);
string data_price = hex.Substring(hex.Length - 64);
return data_price;
}
else
{
// TODO: Error processing
}