500 mg Vitamin D as in the heading contained indicated:
Vitamin D (D3) Cholecalciferol) 1 IU = 0.025 ug ug 1 = 40 IU
500 mg = 500,000 micrograms
500,000 x 40 = 20,000,000 IU of vitamin D per tablet, according to inscription
But there are 2,000 IU or 50 micrograms
ie the entry is an error