2071094
That number is the comment number. For example, I clicked on "Reply" to answer your comment and the comment number appears in my window. It is the 2,0710,094th comment to be posted on the site. It allows the server to find the correct comment when it goes to post notifications. It will turn the number into the poster's name as soon as it is automatically "saved" on the server.

2070376 why is it that when i reply to people i see numbers instead of their name

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