Syntax:
>>

Shifts a longlong (BIGINT) number to the right.

The result is an unsigned 64-bit integer. The value is truncated to 64
bits. In particular, if the shift count is greater or equal to the
width of an unsigned 64-bit number, the result is zero.

URL: http://dev.mysql.com/doc/refman/5.7/en/bit-functions.html

