1. Is this a positive or a negative number?
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000 is the binary representation of a positive integer, on 64 bits (8 Bytes).
In a signed binary, the first bit (the leftmost) is reserved for the sign,
1 = negative, 0 = positive. This bit does not count when calculating the absolute value.
2. Construct the unsigned binary number.
Exclude the first bit (the leftmost), that is reserved for the sign:
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000 = 000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000
3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
262
0 261
0 260
0 259
0 258
0 257
0 256
1 255
0 254
0 253
1 252
0 251
0 250
0 249
1 248
1 247
0 246
1 245
0 244
0 243
0 242
1 241
0 240
1 239
0 238
1 237
1 236
0 235
0 234
1 233
1 232
1 231
1 230
0 229
0 228
0 227
1 226
0 225
0 224
1 223
1 222
0 221
1 220
0 219
1 218
0 217
1 216
1 215
1 214
1 213
0 212
0 211
1 210
1 29
0 28
1 27
1 26
1 25
1 24
0 23
1 22
0 21
0 20
0
4. Multiply each bit by its corresponding power of 2 and add all the terms up.
000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) =
(0 × 262 + 0 × 261 + 0 × 260 + 0 × 259 + 0 × 258 + 0 × 257 + 1 × 256 + 0 × 255 + 0 × 254 + 1 × 253 + 0 × 252 + 0 × 251 + 0 × 250 + 1 × 249 + 1 × 248 + 0 × 247 + 1 × 246 + 0 × 245 + 0 × 244 + 0 × 243 + 1 × 242 + 0 × 241 + 1 × 240 + 0 × 239 + 1 × 238 + 1 × 237 + 0 × 236 + 0 × 235 + 1 × 234 + 1 × 233 + 1 × 232 + 1 × 231 + 0 × 230 + 0 × 229 + 0 × 228 + 1 × 227 + 0 × 226 + 0 × 225 + 1 × 224 + 1 × 223 + 0 × 222 + 1 × 221 + 0 × 220 + 1 × 219 + 0 × 218 + 1 × 217 + 1 × 216 + 1 × 215 + 1 × 214 + 0 × 213 + 0 × 212 + 1 × 211 + 1 × 210 + 0 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 1 × 25 + 0 × 24 + 1 × 23 + 0 × 22 + 0 × 21 + 0 × 20)(10) =
(0 + 0 + 0 + 0 + 0 + 0 + 72 057 594 037 927 936 + 0 + 0 + 9 007 199 254 740 992 + 0 + 0 + 0 + 562 949 953 421 312 + 281 474 976 710 656 + 0 + 70 368 744 177 664 + 0 + 0 + 0 + 4 398 046 511 104 + 0 + 1 099 511 627 776 + 0 + 274 877 906 944 + 137 438 953 472 + 0 + 0 + 17 179 869 184 + 8 589 934 592 + 4 294 967 296 + 2 147 483 648 + 0 + 0 + 0 + 134 217 728 + 0 + 0 + 16 777 216 + 8 388 608 + 0 + 2 097 152 + 0 + 524 288 + 0 + 131 072 + 65 536 + 32 768 + 16 384 + 0 + 0 + 2 048 + 1 024 + 0 + 256 + 128 + 64 + 32 + 0 + 8 + 0 + 0 + 0)(10) =
(72 057 594 037 927 936 + 9 007 199 254 740 992 + 562 949 953 421 312 + 281 474 976 710 656 + 70 368 744 177 664 + 4 398 046 511 104 + 1 099 511 627 776 + 274 877 906 944 + 137 438 953 472 + 17 179 869 184 + 8 589 934 592 + 4 294 967 296 + 2 147 483 648 + 134 217 728 + 16 777 216 + 8 388 608 + 2 097 152 + 524 288 + 131 072 + 65 536 + 32 768 + 16 384 + 2 048 + 1 024 + 256 + 128 + 64 + 32 + 8)(10) =
81 985 529 216 486 888(10)
5. If needed, adjust the sign of the integer number by the first digit (leftmost) of the signed binary:
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) = 81 985 529 216 486 888(10)
The number 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) converted from a signed binary (base two) and written as an integer in decimal system (base ten):
0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1000(2) = 81 985 529 216 486 888(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.