what is /rostopic_10245_1493704203398

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/rostopic_10245_1493704203398 appears when I run rosnode list. Is it by default? The list of number affixed are random or not?

And it has subscriptions of my node.The relevant info of it presents as follows:

Node [/rostopic_10245_1493704203398]
Publications: 
 * /rosout [rosgraph_msgs/Log]

Subscriptions: 
 * /odometry/filtered [nav_msgs/Odometry]

Services: 
 * /rostopic_10245_1493704203398/set_logger_level
 * /rostopic_10245_1493704203398/get_loggers


contacting node http://idriver-ThinkPad-E450:42951/ ...
Pid: 10245
Connections:
 * topic: /rosout
    * to: /rosout
    * direction: outbound
    * transport: TCPROS
 * topic: /odometry/filtered
    * to: /ekf_navigation_node (http://idriver-ThinkPad-E450:39280/)
    * direction: inbound
    * transport: TCPROS

Can someone enlighten it to me?I do appreciate your help.