As of 11/1/2015, no live official trademarks were found on USPTO.gov for the exact term/number
Although this is a long numerical domain, it contains only two distinct numbers: 2 and 8.
In Chinese culture, 2's and 8's are considered to be lucky.
28 = Double prosperity
As an ordinary 9-number domain, this number may mean little to average Occidentals (other than as an easy-to-remember cool pattern); heck, we don't fully understand the premise, either...
This domain is also a palindrome, which means the numbers are the same when read backwards, thus adding another level of mystique to the numerical pattern.
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