[~]$ stat -c %i /
2

[~]$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2             350G   67G  266G  21% /
tmpfs                  12G   44M   12G   1% /dev/shm

[~]$ sudo tune2fs -l /dev/sda2  | grep 'First inode'
First inode:              11