I just received a free singer upright piano that has the number 54906 stamped into the metal on the inside, and I was wondering if anyone could tell me how old it is by that number? Thanks!

It was made about 1908, and it is worth what you paid for it.

rude much?

It's not a matter of being rude, unfortunately it's just reality. Pianos are too big to have any value as collectibles; their only value is as useful musical instruments. And after 100 years, the odds are about 80% or better that they aren't anymore (can't hold tune, dead strings, dead soundboard) and making them so would cost more in labor than the finished instrument would be worth. It's nothing personal, just business.

Ok, well that makes sense. I appologize. I am not really concerned with the value. We consider it a blessing to have a piano at all. I was just wondering how old it was. It is in surprisingly good condition for being over 100 years old. Thank you for the information.

Probaly worth more sentimentally than monetarily, but couldn't hurt to have a tech in your area at least look at it to give you an assessment of it's true health.

That's okay.
It costs $100 +/- 30% to have a piano tuned. Get someone in to give it the once-over and make sure it's something you're going to want to use. Good luck with it.