Convert 4 221 225 078 to a Signed Binary (Base 2)

How to convert 4 221 225 078(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 4 221 225 078 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;
  • 4 221 225 078 ÷ 2 = 2 110 612 539 + 0;
  • 2 110 612 539 ÷ 2 = 1 055 306 269 + 1;
  • 1 055 306 269 ÷ 2 = 527 653 134 + 1;
  • 527 653 134 ÷ 2 = 263 826 567 + 0;
  • 263 826 567 ÷ 2 = 131 913 283 + 1;
  • 131 913 283 ÷ 2 = 65 956 641 + 1;
  • 65 956 641 ÷ 2 = 32 978 320 + 1;
  • 32 978 320 ÷ 2 = 16 489 160 + 0;
  • 16 489 160 ÷ 2 = 8 244 580 + 0;
  • 8 244 580 ÷ 2 = 4 122 290 + 0;
  • 4 122 290 ÷ 2 = 2 061 145 + 0;
  • 2 061 145 ÷ 2 = 1 030 572 + 1;
  • 1 030 572 ÷ 2 = 515 286 + 0;
  • 515 286 ÷ 2 = 257 643 + 0;
  • 257 643 ÷ 2 = 128 821 + 1;
  • 128 821 ÷ 2 = 64 410 + 1;
  • 64 410 ÷ 2 = 32 205 + 0;
  • 32 205 ÷ 2 = 16 102 + 1;
  • 16 102 ÷ 2 = 8 051 + 0;
  • 8 051 ÷ 2 = 4 025 + 1;
  • 4 025 ÷ 2 = 2 012 + 1;
  • 2 012 ÷ 2 = 1 006 + 0;
  • 1 006 ÷ 2 = 503 + 0;
  • 503 ÷ 2 = 251 + 1;
  • 251 ÷ 2 = 125 + 1;
  • 125 ÷ 2 = 62 + 1;
  • 62 ÷ 2 = 31 + 0;
  • 31 ÷ 2 = 15 + 1;
  • 15 ÷ 2 = 7 + 1;
  • 7 ÷ 2 = 3 + 1;
  • 3 ÷ 2 = 1 + 1;
  • 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.

4 221 225 078(10) = 1111 1011 1001 1010 1100 1000 0111 0110(2)


3. Determine the signed binary number bit length:

  • The base 2 number's actual length, in bits: 32.

  • 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, 32,

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:


4 221 225 078(10) Base 10 integer number converted and written as a signed binary code (in base 2):

4 221 225 078(10) = 0000 0000 0000 0000 0000 0000 0000 0000 1111 1011 1001 1010 1100 1000 0111 0110

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