Convert 1 234 567 890 123 449 to a Signed Binary (Base 2)

How to convert 1 234 567 890 123 449(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 1 234 567 890 123 449 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. 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;
  • 1 234 567 890 123 449 ÷ 2 = 617 283 945 061 724 + 1;
  • 617 283 945 061 724 ÷ 2 = 308 641 972 530 862 + 0;
  • 308 641 972 530 862 ÷ 2 = 154 320 986 265 431 + 0;
  • 154 320 986 265 431 ÷ 2 = 77 160 493 132 715 + 1;
  • 77 160 493 132 715 ÷ 2 = 38 580 246 566 357 + 1;
  • 38 580 246 566 357 ÷ 2 = 19 290 123 283 178 + 1;
  • 19 290 123 283 178 ÷ 2 = 9 645 061 641 589 + 0;
  • 9 645 061 641 589 ÷ 2 = 4 822 530 820 794 + 1;
  • 4 822 530 820 794 ÷ 2 = 2 411 265 410 397 + 0;
  • 2 411 265 410 397 ÷ 2 = 1 205 632 705 198 + 1;
  • 1 205 632 705 198 ÷ 2 = 602 816 352 599 + 0;
  • 602 816 352 599 ÷ 2 = 301 408 176 299 + 1;
  • 301 408 176 299 ÷ 2 = 150 704 088 149 + 1;
  • 150 704 088 149 ÷ 2 = 75 352 044 074 + 1;
  • 75 352 044 074 ÷ 2 = 37 676 022 037 + 0;
  • 37 676 022 037 ÷ 2 = 18 838 011 018 + 1;
  • 18 838 011 018 ÷ 2 = 9 419 005 509 + 0;
  • 9 419 005 509 ÷ 2 = 4 709 502 754 + 1;
  • 4 709 502 754 ÷ 2 = 2 354 751 377 + 0;
  • 2 354 751 377 ÷ 2 = 1 177 375 688 + 1;
  • 1 177 375 688 ÷ 2 = 588 687 844 + 0;
  • 588 687 844 ÷ 2 = 294 343 922 + 0;
  • 294 343 922 ÷ 2 = 147 171 961 + 0;
  • 147 171 961 ÷ 2 = 73 585 980 + 1;
  • 73 585 980 ÷ 2 = 36 792 990 + 0;
  • 36 792 990 ÷ 2 = 18 396 495 + 0;
  • 18 396 495 ÷ 2 = 9 198 247 + 1;
  • 9 198 247 ÷ 2 = 4 599 123 + 1;
  • 4 599 123 ÷ 2 = 2 299 561 + 1;
  • 2 299 561 ÷ 2 = 1 149 780 + 1;
  • 1 149 780 ÷ 2 = 574 890 + 0;
  • 574 890 ÷ 2 = 287 445 + 0;
  • 287 445 ÷ 2 = 143 722 + 1;
  • 143 722 ÷ 2 = 71 861 + 0;
  • 71 861 ÷ 2 = 35 930 + 1;
  • 35 930 ÷ 2 = 17 965 + 0;
  • 17 965 ÷ 2 = 8 982 + 1;
  • 8 982 ÷ 2 = 4 491 + 0;
  • 4 491 ÷ 2 = 2 245 + 1;
  • 2 245 ÷ 2 = 1 122 + 1;
  • 1 122 ÷ 2 = 561 + 0;
  • 561 ÷ 2 = 280 + 1;
  • 280 ÷ 2 = 140 + 0;
  • 140 ÷ 2 = 70 + 0;
  • 70 ÷ 2 = 35 + 0;
  • 35 ÷ 2 = 17 + 1;
  • 17 ÷ 2 = 8 + 1;
  • 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.

1 234 567 890 123 449(10) = 100 0110 0010 1101 0101 0011 1100 1000 1010 1011 1010 1011 1001(2)


3. Determine the signed binary number bit length:

  • The base 2 number's actual length, in bits: 51.

  • 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, 51,

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:


1 234 567 890 123 449(10) Base 10 integer number converted and written as a signed binary code (in base 2):

1 234 567 890 123 449(10) = 0000 0000 0000 0100 0110 0010 1101 0101 0011 1100 1000 1010 1011 1010 1011 1001

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