1. Divide the number repeatedly by 2:
Keep track of each remainder.
We stop when we get a quotient that is equal to zero.
- division = quotient + remainder;
- 1 111 001 010 138 ÷ 2 = 555 500 505 069 + 0;
- 555 500 505 069 ÷ 2 = 277 750 252 534 + 1;
- 277 750 252 534 ÷ 2 = 138 875 126 267 + 0;
- 138 875 126 267 ÷ 2 = 69 437 563 133 + 1;
- 69 437 563 133 ÷ 2 = 34 718 781 566 + 1;
- 34 718 781 566 ÷ 2 = 17 359 390 783 + 0;
- 17 359 390 783 ÷ 2 = 8 679 695 391 + 1;
- 8 679 695 391 ÷ 2 = 4 339 847 695 + 1;
- 4 339 847 695 ÷ 2 = 2 169 923 847 + 1;
- 2 169 923 847 ÷ 2 = 1 084 961 923 + 1;
- 1 084 961 923 ÷ 2 = 542 480 961 + 1;
- 542 480 961 ÷ 2 = 271 240 480 + 1;
- 271 240 480 ÷ 2 = 135 620 240 + 0;
- 135 620 240 ÷ 2 = 67 810 120 + 0;
- 67 810 120 ÷ 2 = 33 905 060 + 0;
- 33 905 060 ÷ 2 = 16 952 530 + 0;
- 16 952 530 ÷ 2 = 8 476 265 + 0;
- 8 476 265 ÷ 2 = 4 238 132 + 1;
- 4 238 132 ÷ 2 = 2 119 066 + 0;
- 2 119 066 ÷ 2 = 1 059 533 + 0;
- 1 059 533 ÷ 2 = 529 766 + 1;
- 529 766 ÷ 2 = 264 883 + 0;
- 264 883 ÷ 2 = 132 441 + 1;
- 132 441 ÷ 2 = 66 220 + 1;
- 66 220 ÷ 2 = 33 110 + 0;
- 33 110 ÷ 2 = 16 555 + 0;
- 16 555 ÷ 2 = 8 277 + 1;
- 8 277 ÷ 2 = 4 138 + 1;
- 4 138 ÷ 2 = 2 069 + 0;
- 2 069 ÷ 2 = 1 034 + 1;
- 1 034 ÷ 2 = 517 + 0;
- 517 ÷ 2 = 258 + 1;
- 258 ÷ 2 = 129 + 0;
- 129 ÷ 2 = 64 + 1;
- 64 ÷ 2 = 32 + 0;
- 32 ÷ 2 = 16 + 0;
- 16 ÷ 2 = 8 + 0;
- 8 ÷ 2 = 4 + 0;
- 4 ÷ 2 = 2 + 0;
- 2 ÷ 2 = 1 + 0;
- 1 ÷ 2 = 0 + 1;
2. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
1 111 001 010 138(10) = 1 0000 0010 1010 1100 1101 0010 0000 1111 1101 1010(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 41.
A signed binary's bit length must be equal to a power of 2, as of:
21 = 2; 22 = 4; 23 = 8; 24 = 16; 25 = 32; 26 = 64; ...
The first bit (the leftmost) indicates the sign:
0 = positive integer number, 1 = negative integer number
The least number that is:
1) a power of 2
2) and is larger than the actual length, 41,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 64.
4. Get the positive binary computer representation on 64 bits (8 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 64.
Number 1 111 001 010 138(10), a signed integer number (with sign), converted from decimal system (from base 10) and written as a signed binary in two's complement representation:
1 111 001 010 138(10) = 0000 0000 0000 0000 0000 0001 0000 0010 1010 1100 1101 0010 0000 1111 1101 1010
Spaces were used to group digits: for binary, by 4, for decimal, by 3.