Flight Indira Gandhi International Airport departs from Delhi Indira Gandhi International Airport at 19:15 and arrives at Mumbai Chhatrapati Shivaji International Airport at 21:25.
The flighttime is about 2h 10m. The distance travelled ("as the bird flies"): 544 Km. So the average speed is roughly 251 Km.
The best day to arrive at Delhi is Monday and it would be best to avoid Friday, as prices are on average 18.9% higher than on Monday. (Average prices, based on 4693758 datapoints.)
We have a lot more statistics for flights 6E 354 and between Delhi and Mumbai.