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Number of digits = 4

Total possible number of arrangement = 4 x 4 x 4 x 4 = 256

Group { 1, 2, 3, 4 } as 1 set

⇒ Number of sets = 256 ÷ 4 = 64

Value of 1 set = 1 + 2 + 3 + 4 = 10

⇒ Value of 64 sets = 10 x 64 = 640

At ones place, the sum of all the digits = 640 x 1 =** 640**

At tens place, the sum of all the digits = 640 x 10 =** 6400**

At hundreds place, the sum of all the digits = 640 x 100 = **64000**

At thousands place, the sum of all the digits = 640 x 1000 = **640000**

Total sum = 640000 + 64000 + 6400 + 640 = 711040