[Grammar] Is this your OTHER/ANOTHER phone number?

[Sahil Dhankhar]

What to ask a person when he calls from an unknown number?

:-Is this your OTHER/ANOTHER phone number?

Please reply with detailed answer.


Thank you in advance.

 

[Raymott]

"Is this your other number?"
"Is this another number?" (But you already know this)
"Is this another one of your numbers?"
All of the above are grammatical.