Converting the BIGINT type to a time interval when creating a report

To represent a number as a time interval on a Fast Report layout, add the following function on the Report Layout - Code tab:
public string TicksToString(long ticks) 
    { 
      return new TimeSpan(ticks).ToString(); 
    }
And apply it to the data. To do so, in the text editor specify: 
 
[TicksToString([DataSource.FieldName])]