Convert -123 775 873 255 737 592 to a Signed Binary (Base 2)

How to convert -123 775 873 255 737 592(10), a signed base 10 integer number? How to write it as a signed binary code in base 2

What are the required steps to convert base 10 integer
number -123 775 873 255 737 592 to signed binary code (in base 2)?

  • A signed integer, written in base ten, or a decimal system number, is a number written using the digits 0 through 9 and the sign, which can be positive (+) or negative (-). If positive, the sign is usually not written. A number written in base two, or binary, is a number written using only the digits 0 and 1.

1. Start with the positive version of the number:

|-123 775 873 255 737 592| = 123 775 873 255 737 592

2. Divide the number repeatedly by 2:

Keep track of each remainder.

Stop when you get a quotient that is equal to zero.


  • division = quotient + remainder;
  • 123 775 873 255 737 592 ÷ 2 = 61 887 936 627 868 796 + 0;
  • 61 887 936 627 868 796 ÷ 2 = 30 943 968 313 934 398 + 0;
  • 30 943 968 313 934 398 ÷ 2 = 15 471 984 156 967 199 + 0;
  • 15 471 984 156 967 199 ÷ 2 = 7 735 992 078 483 599 + 1;
  • 7 735 992 078 483 599 ÷ 2 = 3 867 996 039 241 799 + 1;
  • 3 867 996 039 241 799 ÷ 2 = 1 933 998 019 620 899 + 1;
  • 1 933 998 019 620 899 ÷ 2 = 966 999 009 810 449 + 1;
  • 966 999 009 810 449 ÷ 2 = 483 499 504 905 224 + 1;
  • 483 499 504 905 224 ÷ 2 = 241 749 752 452 612 + 0;
  • 241 749 752 452 612 ÷ 2 = 120 874 876 226 306 + 0;
  • 120 874 876 226 306 ÷ 2 = 60 437 438 113 153 + 0;
  • 60 437 438 113 153 ÷ 2 = 30 218 719 056 576 + 1;
  • 30 218 719 056 576 ÷ 2 = 15 109 359 528 288 + 0;
  • 15 109 359 528 288 ÷ 2 = 7 554 679 764 144 + 0;
  • 7 554 679 764 144 ÷ 2 = 3 777 339 882 072 + 0;
  • 3 777 339 882 072 ÷ 2 = 1 888 669 941 036 + 0;
  • 1 888 669 941 036 ÷ 2 = 944 334 970 518 + 0;
  • 944 334 970 518 ÷ 2 = 472 167 485 259 + 0;
  • 472 167 485 259 ÷ 2 = 236 083 742 629 + 1;
  • 236 083 742 629 ÷ 2 = 118 041 871 314 + 1;
  • 118 041 871 314 ÷ 2 = 59 020 935 657 + 0;
  • 59 020 935 657 ÷ 2 = 29 510 467 828 + 1;
  • 29 510 467 828 ÷ 2 = 14 755 233 914 + 0;
  • 14 755 233 914 ÷ 2 = 7 377 616 957 + 0;
  • 7 377 616 957 ÷ 2 = 3 688 808 478 + 1;
  • 3 688 808 478 ÷ 2 = 1 844 404 239 + 0;
  • 1 844 404 239 ÷ 2 = 922 202 119 + 1;
  • 922 202 119 ÷ 2 = 461 101 059 + 1;
  • 461 101 059 ÷ 2 = 230 550 529 + 1;
  • 230 550 529 ÷ 2 = 115 275 264 + 1;
  • 115 275 264 ÷ 2 = 57 637 632 + 0;
  • 57 637 632 ÷ 2 = 28 818 816 + 0;
  • 28 818 816 ÷ 2 = 14 409 408 + 0;
  • 14 409 408 ÷ 2 = 7 204 704 + 0;
  • 7 204 704 ÷ 2 = 3 602 352 + 0;
  • 3 602 352 ÷ 2 = 1 801 176 + 0;
  • 1 801 176 ÷ 2 = 900 588 + 0;
  • 900 588 ÷ 2 = 450 294 + 0;
  • 450 294 ÷ 2 = 225 147 + 0;
  • 225 147 ÷ 2 = 112 573 + 1;
  • 112 573 ÷ 2 = 56 286 + 1;
  • 56 286 ÷ 2 = 28 143 + 0;
  • 28 143 ÷ 2 = 14 071 + 1;
  • 14 071 ÷ 2 = 7 035 + 1;
  • 7 035 ÷ 2 = 3 517 + 1;
  • 3 517 ÷ 2 = 1 758 + 1;
  • 1 758 ÷ 2 = 879 + 0;
  • 879 ÷ 2 = 439 + 1;
  • 439 ÷ 2 = 219 + 1;
  • 219 ÷ 2 = 109 + 1;
  • 109 ÷ 2 = 54 + 1;
  • 54 ÷ 2 = 27 + 0;
  • 27 ÷ 2 = 13 + 1;
  • 13 ÷ 2 = 6 + 1;
  • 6 ÷ 2 = 3 + 0;
  • 3 ÷ 2 = 1 + 1;
  • 1 ÷ 2 = 0 + 1;

3. Construct the base 2 representation of the positive number:

Take all the remainders starting from the bottom of the list constructed above.

123 775 873 255 737 592(10) = 1 1011 0111 1011 1101 1000 0000 0011 1101 0010 1100 0000 1000 1111 1000(2)


4. Determine the signed binary number bit length:

  • The base 2 number's actual length, in bits: 57.

  • 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) is reserved for 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, 57,

3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)


=== is: 64.


5. 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:


123 775 873 255 737 592(10) = 0000 0001 1011 0111 1011 1101 1000 0000 0011 1101 0010 1100 0000 1000 1111 1000

6. Get the negative integer number representation:

To get the negative integer number representation on 64 bits (8 Bytes),


... change the first bit (the leftmost), from 0 to 1...


-123 775 873 255 737 592(10) Base 10 integer number converted and written as a signed binary code (in base 2):

-123 775 873 255 737 592(10) = 1000 0001 1011 0111 1011 1101 1000 0000 0011 1101 0010 1100 0000 1000 1111 1000

Spaces were used to group digits: for binary, by 4, for decimal, by 3.

How to convert signed base 10 integers in decimal to binary code system

Follow the steps below to convert a signed base ten integer number to signed binary:

  • 1. In a signed binary, first bit (the leftmost) is reserved for sign: 0 = positive integer number, 1 = positive integer number. If the number to be converted is negative, start with its positive version.
  • 2. Divide repeatedly by 2 the positive integer number keeping track of each remainder. STOP when we get a quotient that is ZERO.
  • 3. Construct the base 2 representation of the positive number, by taking all the remainders starting from the bottom of the list constructed above. Thus, the last remainder of the divisions becomes the first symbol (the leftmost) of the base two number, while the first remainder becomes the last symbol (the rightmost).
  • 4. Binary numbers represented in computer language have a length of 4, 8, 16, 32, 64, ... bits (power of 2) - if needed, fill in extra '0' bits in front of the base 2 number (to the left), up to the right length; this way the first bit (the leftmost one) is always '0', as for a positive representation.
  • 5. To get the negative reprezentation of the number, simply switch the first bit (the leftmost one), from '0' to '1'.

Example: convert the negative number -63 from decimal system (base ten) to signed binary code system:

  • 1. Start with the positive version of the number: |-63| = 63;
  • 2. Divide repeatedly 63 by 2, keeping track of each remainder, until we get a quotient that is equal to zero:
    • division = quotient + remainder
    • 63 ÷ 2 = 31 + 1
    • 31 ÷ 2 = 15 + 1
    • 15 ÷ 2 = 7 + 1
    • 7 ÷ 2 = 3 + 1
    • 3 ÷ 2 = 1 + 1
    • 1 ÷ 2 = 0 + 1
  • 3. Construct the base 2 representation of the positive number, by taking all the remainders starting from the bottom of the list constructed above:
    63(10) = 11 1111(2)
  • 4. The actual length of base 2 representation number is 6, so the positive binary computer representation length of the signed binary will take in this case 8 bits (the least power of 2 higher than 6) - add extra '0's in front (to the left), up to the required length; this way the first bit (the leftmost one) is to be '0', as for a positive number:
    63(10) = 0011 1111(2)
  • 5. To get the negative integer number representation simply change the first bit (the leftmost), from '0' to '1':
    -63(10) = 1011 1111
  • Number -63(10), signed integer, converted from decimal system (base 10) to signed binary = 1011 1111