According to a Wikipedia entry, 35 is a discrete semiprime (or biprime) (5 × 7); the tenth, and the first with 5 as the lowest non-unitary factor. The aliquot sum of 35 is 13 this being the second composite number with such an aliquot sum; the first being the cube 27. 35 is the last member of the first triple cluster of semiprimes 33, 34, 35. 85, 86, 87 is the second such triple discrete semiprime cluster.
For those of you scratching your heads wondering what this all means, in simpler terms it represents 35 million, the number of concurrent users who were just on Skype, just one week after announcing our milestone of 34 million users concurrently online . We at Skype are so excited to see more and more people choosing Skype around the world every day, sharing special moments with friends, family and co-workers across borders. If you’re one of the 35 million users who logged on today to take part in this milestone, share with us on Twitter how you used Skype by using the hashtag #ILoveSkype.