Sir, 21 mukhi is very good from health point of view. It controls and cures all related to reproductive organ. 21 mukhi rudraksha is very good Hindu symbol of spirituality. It represents lord Shiva himself with more power. It is for every success in life and fertility.
The price of the bead depends on the availability. It is actually above 14 lakh INR. But it takes time to procure it and verify it. So a search in advance is required for this bead to get the proper and quality bead.