Power Rating.
Power rating is considered the total stat points of all 6 attributes multiplied by the ascension of their destiny. It is temporary destiny x permanent destiny x tier.
Power is not absolute, as the effects of abilities influence the outcomes in battle. So power is just a means to categorize people based on potential danger.
No. Rank: Total Stat
0. Unranked: Less than 1,000.
1. F: Above 1,000 (Thousand Mark).
2. E: Above 10,000.
3. D: Above 100,000.
4. C: Above 1,000,000 (Million Mark).
5. B: Above 10,000,000.
6. A: Above 100,000,000.
7. S: Above 1,000,000,000 (Billion Mark).
8. SS: Above 10,000,000,000.
9. SSS: Above 100,000,000,000.
10. X: Above 1,000,000,000,000 (Trillion Mark).
Note that this doesn't take into account the power of Demigods.
Power rating and ability form the bulk of the power of a super. As for abilities, they are divided into Omega, Alpha, and Beta which depends on how well they scale with power rating.
Gifts
-- Gift
received Weekly Power Status
-- Power
Ranking 
-- Power
stone