You got me, I don't.
Probably means the wearer either saw, or has a friend who saw, the musical Rent. I saw that show in Chicago with then-girlfriend in 1998, and in the lobby during intermission there were scarfs for sale with "525,600" knit into them in very large numbers. I asked my wife what that was for (she had listened to the soundtrack; I hadn't) and she suggested I'd figure it out in Act II.
Sure enough, the first song after intermission, "Seasons of Love", opened with the answer: "Five hundred twenty-five thousand six hundred minutes. Five hundred twenty-five thousand moments so dear. Five hundred twenty-five thousand six hundred minutes. How do you measure--measure a year?"