What is the significance of 786 in Islam. Does this stand for Bismillah Hirrahmanir Raheem.

786 is not a substitute for Bismillah Hirrahman Nirraheem. i.e. if someone writes 786 then he still have to say and write Bismillah Hirrahman Nirraheem. But it is allowed and permissible to write this with that intention; and it is also permissible to use this with the intention of gaining blessing (Barkaat)
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