Can Someone Hack into Bank Account if they know your Aadhaar Number?

No, Just like similar scenario by knowing ATM Card Number no one can withdraw cash from ATM Machine, similarly by knowing your Aadhaar Number along no one could hack into your bank account or withdraw money from your bank account.

Can Someone Hack into Bank Account if they know your Aadhaar Number?

Your bank account is safe and secure until and unless you don't share your PIN/ OTP given by banks. Rest assured, till date there has been no single cases of financial loss reported due to Aadhaar.