yes anything can be hacked and it possible the whole world can be hacked . Any thing in this world that is an electronic device and connected to the INTERNET can be hacked any device take example of phones,computer,laptops,tablets,smart watch,traffic light,television ,satellite,cars,radio,wifi and any device connected to that wifi,drones,robots so the list is uncountless so if you hacked satellite u can possible hack any television networks sub satellite connected to it . And if u hack networking operation company database u can hack any device register with that network company and if you have many digital devices with u.You can form botnets with that group of devices and do ddos ( distributed denial of service ) attack  and can  shut down any website u want bur it should be enough to generate byte load to shut down that website you can even possible hack any nuclear warfare station and NASA base station with much advance hacking software and attacks like back door , rat ,ddos,MITM attacks and if u hack a device with a malware it can be passed to other and make a chain reaction

so if you want to be safe : note you cant be safe from hackers