What does it mean
Please elaborate your issue so that we can help you better.
Also, please provide a screenshot of the page where you are seeing this yellow circle with the number.
I realized that I had uploaded a photo with lots of noise, so I got a yellow circle with #1 on it.
Was there a message besides the number? Please upload a screen shot so we can let you know. If the image was excessively noisy you could have prompted a warning message indicating the file would likely be rejected by our moderators due to poor quality. It gives you an opportunity to delete the file before spending too much time submitting it.