Convert -1 090 571 713 984 699 to a Signed Binary in Two's (2's) Complement Representation

How to convert decimal number -1 090 571 713 984 699(10) to a signed binary in two's (2's) complement representation

What are the steps to convert decimal number
-1 090 571 713 984 699 to a signed binary in two's (2's) complement representation?

  • 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:

|-1 090 571 713 984 699| = 1 090 571 713 984 699

2. 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;
  • 1 090 571 713 984 699 ÷ 2 = 545 285 856 992 349 + 1;
  • 545 285 856 992 349 ÷ 2 = 272 642 928 496 174 + 1;
  • 272 642 928 496 174 ÷ 2 = 136 321 464 248 087 + 0;
  • 136 321 464 248 087 ÷ 2 = 68 160 732 124 043 + 1;
  • 68 160 732 124 043 ÷ 2 = 34 080 366 062 021 + 1;
  • 34 080 366 062 021 ÷ 2 = 17 040 183 031 010 + 1;
  • 17 040 183 031 010 ÷ 2 = 8 520 091 515 505 + 0;
  • 8 520 091 515 505 ÷ 2 = 4 260 045 757 752 + 1;
  • 4 260 045 757 752 ÷ 2 = 2 130 022 878 876 + 0;
  • 2 130 022 878 876 ÷ 2 = 1 065 011 439 438 + 0;
  • 1 065 011 439 438 ÷ 2 = 532 505 719 719 + 0;
  • 532 505 719 719 ÷ 2 = 266 252 859 859 + 1;
  • 266 252 859 859 ÷ 2 = 133 126 429 929 + 1;
  • 133 126 429 929 ÷ 2 = 66 563 214 964 + 1;
  • 66 563 214 964 ÷ 2 = 33 281 607 482 + 0;
  • 33 281 607 482 ÷ 2 = 16 640 803 741 + 0;
  • 16 640 803 741 ÷ 2 = 8 320 401 870 + 1;
  • 8 320 401 870 ÷ 2 = 4 160 200 935 + 0;
  • 4 160 200 935 ÷ 2 = 2 080 100 467 + 1;
  • 2 080 100 467 ÷ 2 = 1 040 050 233 + 1;
  • 1 040 050 233 ÷ 2 = 520 025 116 + 1;
  • 520 025 116 ÷ 2 = 260 012 558 + 0;
  • 260 012 558 ÷ 2 = 130 006 279 + 0;
  • 130 006 279 ÷ 2 = 65 003 139 + 1;
  • 65 003 139 ÷ 2 = 32 501 569 + 1;
  • 32 501 569 ÷ 2 = 16 250 784 + 1;
  • 16 250 784 ÷ 2 = 8 125 392 + 0;
  • 8 125 392 ÷ 2 = 4 062 696 + 0;
  • 4 062 696 ÷ 2 = 2 031 348 + 0;
  • 2 031 348 ÷ 2 = 1 015 674 + 0;
  • 1 015 674 ÷ 2 = 507 837 + 0;
  • 507 837 ÷ 2 = 253 918 + 1;
  • 253 918 ÷ 2 = 126 959 + 0;
  • 126 959 ÷ 2 = 63 479 + 1;
  • 63 479 ÷ 2 = 31 739 + 1;
  • 31 739 ÷ 2 = 15 869 + 1;
  • 15 869 ÷ 2 = 7 934 + 1;
  • 7 934 ÷ 2 = 3 967 + 0;
  • 3 967 ÷ 2 = 1 983 + 1;
  • 1 983 ÷ 2 = 991 + 1;
  • 991 ÷ 2 = 495 + 1;
  • 495 ÷ 2 = 247 + 1;
  • 247 ÷ 2 = 123 + 1;
  • 123 ÷ 2 = 61 + 1;
  • 61 ÷ 2 = 30 + 1;
  • 30 ÷ 2 = 15 + 0;
  • 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:

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

1 090 571 713 984 699(10) = 11 1101 1111 1101 1110 1000 0011 1001 1101 0011 1000 1011 1011(2)

4. Determine the signed binary number bit length:

  • The base 2 number's actual length, in bits: 50.

  • 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, 50,

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.


1 090 571 713 984 699(10) = 0000 0000 0000 0011 1101 1111 1101 1110 1000 0011 1001 1101 0011 1000 1011 1011

6. Get the negative integer number representation. Part 1:

  • To write the negative integer number on 64 bits (8 Bytes), as a signed binary in one's complement representation, replace all the bits on 0 with 1s and all the bits set on 1 with 0s.

Reverse the digits, flip the digits:

Replace the bits set on 0 with 1s and the bits set on 1 with 0s.

!(0000 0000 0000 0011 1101 1111 1101 1110 1000 0011 1001 1101 0011 1000 1011 1011)


= 1111 1111 1111 1100 0010 0000 0010 0001 0111 1100 0110 0010 1100 0111 0100 0100


7. Get the negative integer number representation. Part 2:

  • To write the negative integer number on 64 bits (8 Bytes), as a signed binary in two's complement representation, add 1 to the number calculated above 1111 1111 1111 1100 0010 0000 0010 0001 0111 1100 0110 0010 1100 0111 0100 0100 (to the signed binary in one's complement representation).

Binary addition carries on a value of 2:

  • 0 + 0 = 0
  • 0 + 1 = 1
  • 1 + 1 = 10
  • 1 + 10 = 11
  • 1 + 11 = 100

Add 1 to the number calculated above
(to the signed binary number in one's complement representation):

-1 090 571 713 984 699 =

1111 1111 1111 1100 0010 0000 0010 0001 0111 1100 0110 0010 1100 0111 0100 0100 + 1


Decimal Number -1 090 571 713 984 699(10) converted to signed binary in two's complement representation:

-1 090 571 713 984 699(10) = 1111 1111 1111 1100 0010 0000 0010 0001 0111 1100 0110 0010 1100 0111 0100 0101

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


How to convert signed integers from decimal system to signed binary in two's complement representation

Follow the steps below to convert a signed base 10 integer number to signed binary in two's complement representation:

  • 1. If the number to be converted is negative, start with the positive version of the number.
  • 2. Divide repeatedly by 2 the positive representation of the integer number, keeping track of each remainder, until 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 must have 4, 8, 16, 32, 64, ... bit length (a power of 2) - if needed, add extra bits on 0 in front (to the left) of the base 2 number above, up to the required length, so that the first bit (the leftmost) will be 0, correctly representing a positive number.
  • 5. To get the negative integer number representation in signed binary one's complement, replace all 0 bits with 1s and all 1 bits with 0s (reversing the digits).
  • 6. To get the negative integer number, in signed binary two's complement representation, add 1 to the number above.

Example: convert the negative number -60 from the decimal system (base ten) to signed binary in two's complement:

  • 1. Start with the positive version of the number: |-60| = 60
  • 2. Divide repeatedly 60 by 2, keeping track of each remainder:
    • division = quotient + remainder
    • 60 ÷ 2 = 30 + 0
    • 30 ÷ 2 = 15 + 0
    • 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:
    60(10) = 11 1100(2)
  • 4. Bit length of base 2 representation number is 6, so the positive binary computer representation of a signed binary will take in this particular case 8 bits (the least power of 2 larger than 6) - add extra 0 digits in front of the base 2 number, up to the required length:
    60(10) = 0011 1100(2)
  • 5. To get the negative integer number representation in signed binary one's complement, replace all the 0 bits with 1s and all 1 bits with 0s (reversing the digits):
    !(0011 1100) = 1100 0011
  • 6. To get the negative integer number, signed binary in two's complement representation, add 1 to the number above:
    -60(10) = 1100 0011 + 1 = 1100 0100
  • Number -60(10), signed integer, converted from decimal system (base 10) to signed binary two's complement representation = 1100 0100