South Africa clinched the five match series 3-2.
South Africa, opting to bat first in the series decider, put up a mammoth 438/4 in their 50 overs.
Faf du Plessis was the top scorer as he made 133 runs with the help of nine fours and six sixes before he was retired hurt.
AB de Villiers, smashing the Indian bowlers to all parts of the Wankhede Stadium, made 119 runs as he hit 11 sixes and only three fours.
Opener De Kock made 109 runs which included 17 boundaries and six sixes to his name.
Hashim Amla made 23 runs while David Miller made an unbeaten 22 runs for the team.
Indian bowlers Bhuvneshwar Kumar, Mohit Sharma, Harbhajan Singh and Suresh Raina all dismissed one batsman each.
India were back in the pavilion after being all out in 224 in 36 overs.
Ajinkya Rahane made 87 runs whereas Shikhar Dhawan made 60 runs for the team. Suresh Raina contributed 27 runs for the side whereas Rohit Sharma made 16 runs.
Kagiso Rabada took four wickets whereas Dale Steyn dismissed three batsmen. Imran Tahir grabbed two wickets whereas Kyle Abbott dismissed one batsman as well.