Peter customises the Sender ID (like the Caller ID) to show his businessname. He doesn't need replies and preferred not to use our 'shared numbers'..and that's perfectly fine.
But Peter called with an odd support question..."what is this phone number that shows up on my iPhone when I look at the Message Details?".
I tested on the Galaxy..nope. Couldn't see it. But on the iPhone, yes we could replicate the issue!
To illustrate, I sent a test SMS to my iPhone using the SenderID iphonebug. Here's 2 screenshots from my phone:
Above image is the SMS received on my iphone "from" iphonebug" SenderID.
And below is what iPhone thinks the "underlying" phone number is when you click the info icon:
...and if you convert the numbers 474663284 into their letter equivalent, it spells out iphonebug !
You learn something new every day!