How can I check my device model number?
If you are unsure of your Nokia device model number, you can check it easily by turning your device off and then removing the battery. The model number is printed on the white label underneath and can be found next to MODEL.
How can I check for new software?
To find out if new software is available for your particular Nokia device model, you need to know your device product number.
Turn the Nokia device off
Remove the battery from your Nokia device to read the 7-digit product code located on the white label as shown below:
Check if new software is available for your device at Device software update or your local Nokia website and enter the product code into the field at Step 2/2: See if there's an update.
Please note that your mobile service provider, operator, or carrier may not have approved the latest Nokia device firmware available.
Nokia produces many different variants of each product (for different countries and languages) and not all variants have the latest Nokia device firmware. It is our priority to update all variants as quickly as possible, and we apologize for any delay. New software may become available at a later date, however, so please check back soon.

article taken from nokia web