Android OS - strange UDP traffic on port 123

I have a Redmi Note 3 (unrooted) phone running MIUI Global 10.2 [Android version 6.0.1 MMB29M] I have installed AdGuard to monitor the traffic that my phone sends/receives. While checking the 'Filtering Log', I see few connections that the app "Android OS" makes to the remote address "118.189.138.5:123" (see screenshot). As you can see from the screenshot, the requested URL is having a "UDP" connection protocol. Now, when I do a search for this IP address, I see that it belongs to "M1 Connect Pte Ltd" in Singapore. https://www.speedguide.net/ip/118.189.138.5 I also noticed similar UDP connections to these IP addresses: 95.216.192.15 belongs to "D2 Internet Investment Ukraine ETTH broadband" in Ukraine 133.243.238.163 belongs to "National Institute of Information and Communicatio" in Japan and the strangest of all 202.12.97.45 belonging to "Ministry of University Affairs" in Thailand So my question is why would Android OS make connection to this IP addresses. What are these connections for? Am I missing something here or are these some legit connections used for some 'good' work? Is my phone connecting and leaking some information? Hoping that some expert on networking will answer this.