Devices with cryptic names (hangzhou device) and Chinese ip addresses connected to my router

These are not real devices. Your network device has some sort of memory fault and is displaying memory as "addresses". You can see that the device names contain sections of some JavaScript-like code. The IP and MAC addresses, when ASCII-decoded, show similar data: Not coincidentally, the "BC:3B:" in the last address is the same as the beginning of your first MAC address listed, which @Anti-weakpasswords notes belong to an Apple device. I would recommend rebooting your device and checking for any available firmware updates from NETGEAR.

How to Tell What Unknown Devices like Hangzhou device are Connected to Your Router

 1) Navigate to the IP address for the router's administrative app. This IP address is usually 192.168.0.1 or 192.168.1.1. Many Netgear routers also use the domain name routerlogin.net for the administrative interface.

 2) Log in with the administrative username and password. Refer to the router’s user manual for the defaults for these credentials.

3) Click the “Status” option in the top navigation bar of the Linksys interface, click “Local Network,” and then click “DHCP Clients Table.” This table identifies all devices connected to the router by the device name, IP address, and MAC address. On a Netgear   router, click the “Attached Devices” link in the left navigation panel under the Maintenance heading. The Attached Devices table opens, displaying the device name, IP address, and MAC address of each connected device.