Can i find my iphone if i dont know the phone number

If you've lost or misplaced an Apple device or personal item, just use the Find My app on your iPhone, iPad or iPod touch with the latest version of iOS or iPadOS, or Mac with the latest version of macOS signed in with the same Apple ID. You can also use the Find Devices or Find Items apps on your Apple Watch with the latest version of watchOS. 

For a misplaced iPhone, iPad, iPod touch, Apple Watch, Mac, AirPods product or supported Beats product, you can also use the Find My app on a device owned by someone in your Family Sharing group, or sign in to iCloud.com/find on a web browser.

This document has a list of things to do if your iPhone, iPad, or iPod touch is lost or stolen. --> If your iPhone, iPad, or iPod touch is lost or stolen - Apple Support

- The Find My service described in the article is the only recovery feature Apple offers. It must be set up before the device is lost. It does not use a phone number.

Read this document for how to use the Find My app to locate a missing device or item --> Use the Find My app to locate a missing device or item - Apple Support

The chances of locating a device depend upon which features you selected in:

Set up Find My on your iPhone, Mac, and other devices - Set up Find My on your iPhone, iPad, iPod touch, or Mac - Apple Support