Go look at yourself in the mirror. Do you see a number stamped on your forehead? Unless an individual has been monitored 24/7 since (s)he hit puberty, there's no way of knowing how many persons that individual has slept with. Women aren't interested in numbers per se, they're interested in meeting confident and socially savvy men.

If you're a guy who's social, cool and fun to hang around with, people will tend to assume that you've slept with more than a few women. If you on the other hand come off as a bitter and angry person, most people will think that your "number" is low or non-existant, because you're displaying some very unattractive traits.