Maybe this can help? These are common actions carried out over the UDP protocol (the numbers are port numbers)
53
domain
Domain Name Server (DNS)
Uses a simple request/reply messaging system for most exchanges (but also uses TCP for longer ones).
67 and 68
bootps / bootpc
Bootstrap Protocol (BOOTP) and Dynamic Host Configuration Protocol (DHCP)
Host configuration protocols that consist of short request and reply exchanges.
69
tftp
Trivial File Transfer Protocol (TFTP)
TFTP is a great example of a protocol that was specifically designed for UDP, especially when it is compared to regular FTP. The latter protocol uses TCP to establish a session between two devices, and then makes use of its own large command set and TCP's features to ensure reliable transfer of possibly very large files. In contrast, TFTP is designed for the quick and easy transfer of small files. It includes simple versions of some of TCP's features, such as acknowledgments, to avoid file corruption.
161 and 162
snmp
Simple Network Management Protocol
An administrative protocol that uses relatively short messages.
520 and 521
router / ripng
Routing Information Protocol (RIP-1, RIP-2, RIPng)
Unlike more complex routing protocols like BGP, RIP uses a simple request/reply messaging system, doesn't require connections, and does require multicasts/broadcasts. This makes it a natural choice for UDP. If a routing update is sent due to a request and is lost, it can be replaced by sending a new request. Routine (unsolicited) updates that are lost are replaced in the next cycle.
2049
nfs
Network File System
NFS is an interesting case. Since it is a file sharing protocol, one would think that it would use TCP instead of UDP, but it was originally designed to use UDP for performance reasons. There were many people who felt this was not the best design decision, and later versions moved to the use of TCP. The latest version of NFS uses only TCP.
As For your IP address it seems to belong to Utorrent?