The mobile number and email values are returned in Aadhaar KYC API, but in hashed format. The hash cannot be used to find out an individual's contact details. 

If the user has shared the mobile number and email ID linked to their Aadhaar number, you would be able to cross-verify by hashing these values and comparing them with the output of Aadhaar KYC API. Please refer to this link for details of hashing performed by UIDAI.