2TB pendrive showing only 1.39 TB of free space

[sumedh07]

My new 2TB pendrive is showing only 1.39 TB of free space while the remaining space appears to be occupied. What is the exact problem? Is there any inbuilt software or something?
It has no folder or file which I installed on it.

 

[popatim]

it could be, some usb drive do have built in software in a hidden partitions, like U3 enabled drives for example.