Find the missing number in the given number series? 2676, 445, ?, 21,6, 2, 1

The given number series 2676, 445, ?, 21,6, 2, 1 follows a pattern that,

From right side,

1

1 x 1 + 1 = 2

2 x 2 + 2 = 6

6 x 3 + 3 = 21

21 x 4 + 4 = 88

88 x 5 + 5 = 445

445 x 6 + 6 = 2676

Hence the missing number in the given number series is 88.