My other favorite fun fact about this number (other than this new prime info which I am excited to have learned) is that in almost every store I’ve tried it, someone has used that (along with a local area code) as the phone number for a store loyalty card.
I’m a Bay Area guy, so if you’re ever at Safeway and need to get the discount without giving up your personal info, 415-867-5309 has got ya covered ;)
> someone has used that (along with a local area code) as the phone number for a store loyalty card.
Usually because for far too long, noisy retailers wanted a "phone number" upon checkout (even if one was paying cash -- Radio Shack was an especially bad one back in the day). For those who didn't want to get yet more telemarketing calls, repeating "Jenny's number" [1] from the song was a way to "just buy" whatever it was you wanted. The minimum wage cashier didn't care, but the cash register demanded "a number". So giving the cashier Jenny's number worked.
This has largely faded now that they can track everyone via one's credit card numbers.
There's a conceptually linked concept called the PAR (Payment Account Reference) which some payment systems return.
You can't transact with it directly, but theoretically it refers to the same payment instrument whether you accessed it by the 16-digit PAN on the card, a mobile wallet that generates a new dPAN each time, or a token that corresponds to a secure vault platform.
It's useful for things like transit payments where someone might tap their card when entering the train and their phone when exiting, and they need to treat them as equivalent for "fares for a single traveller/card can be no more than $x per day"
If a given retailer gets the same number off your card each time you do contactless, then that retailer /could/ track you via that number.
If all retailers get the same number, then they can each track you, and correlate your purchases between themselves.
Note, there just needs to be /some/ constant number from whatever comes through via contactless, the number does not have to be the magic numbers that post the sale to the card.
You can use the number with your local area code just about anywhere at the pump to get a gas discount as well (a common loyalty reward program benefit).
I’m a Bay Area guy, so if you’re ever at Safeway and need to get the discount without giving up your personal info, 415-867-5309 has got ya covered ;)