2. Multiply each bit by its corresponding power of 2 and add all the terms up.
11 1000 0001 0000 0000 1101(2) =
(1 × 221 + 1 × 220 + 1 × 219 + 0 × 218 + 0 × 217 + 0 × 216 + 0 × 215 + 0 × 214 + 0 × 213 + 1 × 212 + 0 × 211 + 0 × 210 + 0 × 29 + 0 × 28 + 0 × 27 + 0 × 26 + 0 × 25 + 0 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20)(10) =
(2 097 152 + 1 048 576 + 524 288 + 0 + 0 + 0 + 0 + 0 + 0 + 4 096 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 8 + 4 + 0 + 1)(10) =
(2 097 152 + 1 048 576 + 524 288 + 4 096 + 8 + 4 + 1)(10) =
3 674 125(10)
The number 11 1000 0001 0000 0000 1101(2) converted from an unsigned binary (in base 2) and written as a positive integer (with no sign) in decimal system (in base ten):
11 1000 0001 0000 0000 1101(2) = 3 674 125(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.