Noun + 号码
The noun 号码 (hàomǎ) means "number" in the sense of an assigned code or identifier, such as a phone number, room number, or tracking number. It differs from 数字 (numeral/digit) in that 号码 specifically refers to a number used for identification purposes.
你能把你的手机号码发给我吗?
Nǐ néng bǎ nǐ de shǒujī hàomǎ fā gěi wǒ ma?
Can you send me your phone number?
我忘记了房间号码,得去前台问一下。
Wǒ wàngjìle fángjiān hàomǎ, děi qù qiántái wèn yíxià.
I forgot the room number; I need to go ask at the front desk.
请输入验证码旁边的号码完成注册。
Qǐng shūrù yànzhèngmǎ pángbiān de hàomǎ wánchéng zhùcè.
Please enter the number next to the verification code to complete registration.