Convert each amount of grams into moles:
I: 23.24g x 1 mol / 126.90g = 0.1831 mol I
C: 2.198 x 1 mol / 12.01g = 0.1830 mol C
N: 2.562 x 1 mol / 14.01g = 0.1829 mol N
Each element has roughly the same amount of moles, which means the whole number ratio between the elements is 1:1:1
Therefore the empirical formula is ICN
