"Oh, I have so much to tell you".

The riddle below was discussed in one of the chat rooms but it is not clear yet what, if anything it is related to.

From: "[email protected]"

"Oh, I have so much to tell you".

Who is the fifth man?
So many Numb3rs exist in this world,
But who holds the key?
13, blank, blank, blank, blank, blank, blank, blank, blank, 28.
And which is the sacred number?
You tell me.

01:18 Esteed Did anybody else just get a weird email?

There's a photo attached, I'm redownloading camo now.
The photo file is titled "irememberyou". It's two old guys sitting around talking, and on the chest of one is that same phrase.