Lost Iphone6

I have lost my Iphone6. I don't have the IMEI number. How can I get the IMEI number. I need IMEI number in order to do a case in police. Without IMEI number police won't accept my general dairy of a lost phone. Can you please help me with it. In iCloud last 5 numbers of IMEI shown. To do a case/general dairy in police I need the full degits of IEMI number.