Dial 121 from your Airtel SIM and follow the IVR options to hear your number
Dial *121# and check the displayed menu for your number
Dial *282# to see your Airtel mobile number on the screen
Call or send a missed call to another phone and check the caller ID
Open the Airtel Thanks app and view your registered mobile number
Check the SIM card pack or documents if you still have them
Go to an Airtel store with a valid ID to confirm your number