TechnoSlab

Just dial *140*1600# form your Airtel SIM card whose number you want to know

You can alternatively try these numbers too : *140*6575# or *140*657#

After dialing, you'll get a call from your own number. Enjoy !!
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Send a blank SMS to 59103 (toll free number ).
New method ( tested )

This is really funny but I was shocked to see that it works.

To know your number, goto this link. It's will show an error that the content doesn't exist and also display your mobile number.

Here's the link : http://202.87.41.147/waphung/wappush_download/1005/KatrinaKaif.gif