Present radio, mm and optical afterglow data along with that published in the literature has been used to study the nature of this brightest explosion. The numerical fit to the multi‐wavelength data constraints the values of the physical parameters and the emission mechanism of the burst. It has been found that the observed decay nature of the afterglow fits equally good with both the ISM and WIND density profiles of the circum‐burst. Using the results from our analysis we derive the value of blast‐wave size to be ∼1018 cm and the value of the Lorentz factor to be ∼300.