Question Summary:
What is the meaning of 786 in Islam?

Question Detail:

What is the meaning of 786 in Islam? Someone told me that means " hare rame Hare Krishna"

Answer :

In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
The numerals 786 are both used in Islam and in Hinduism. In Islam it is supposed to indicate towards 'Bismillah Hirahmaani Raaheem'(بسم الله الرحمان الرحيم) whilst in Hinduism it is the equivalent of what you were told.
786 is derived by numerical calculations called Abjad in the Arabic language. This science is similar to Gematria in which a letter is given a value which is then added up to give the final figure. For a brief understanding of how the Arabic Abjad is calculated to its power in numerals you may refer to: http://askimam.org/public/question_detail/3165.html
Principally, speaking 786 has no Sharee basis and nor does one get the reward of writing 'Bismillah Hirahmaani Raaheem'(بسم الله الرحمان الرحيم) by writing 786. [1]However, there is no prohibition in using it and nor is it an imitation of the Hindu perception of 786. 
And Allah Ta’āla Knows Best
Ismail Dawoodjee
Student Darul Iftaa
Zambia
Checked and Approved by,
Mufti Ebrahim Desai.
www.daruliftaa.net
فتاوى محمودية ج7 ص247 مكتبة محمودية