The oxidation number of Li in LiNO2 is +1. This is because Li is in Group 1 of the periodic table and therefore loses one electron to achieve a noble gas configuration. The oxidation number of N in LiNO2 is +5. This is because N is in Group 5A of the periodic table and therefore gains three electrons to achieve a noble gas configuration. The oxidation number of O in LiNO2 is -2. This is because O is in Group 6A of the periodic table and therefore gains two electrons to achieve a noble gas configuration.

The overall oxidation number of LiNO2 is 0. This is because the sum of the oxidation numbers of all the atoms in a compound must be equal to the charge of the compound. LiNO2 is a neutral compound, so its overall oxidation number is 0.