and there are some potential drawbacks which may not actually improve your situation (such as getting a 'new' number which has an unwelcome history attached to it).
Consider getting a call screening device, or a phone which does this, instead.
The device/phone intercepts the incoming call and requires responses from the caller (usually to press a certain key and/or say who they are). Only if they do that does the call go through to your home phone. The automated calls are not able to respond to this so the call is dropped without ringing your phone. Devices which only block individual numbers are no use as the incoming fake caller IDs keep changing.
This approach also means you don't have to update your contacts of a change of number. Look at devices from trueCall, CPR Call Blocker and cordless phone ranges from BT.