Convert 410 075 007 400 646 to a Signed Binary in Two's (2's) Complement Representation

How to convert decimal number 410 075 007 400 646(10) to a signed binary in two's (2's) complement representation

What are the steps to convert decimal number
410 075 007 400 646 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. 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;
  • 410 075 007 400 646 ÷ 2 = 205 037 503 700 323 + 0;
  • 205 037 503 700 323 ÷ 2 = 102 518 751 850 161 + 1;
  • 102 518 751 850 161 ÷ 2 = 51 259 375 925 080 + 1;
  • 51 259 375 925 080 ÷ 2 = 25 629 687 962 540 + 0;
  • 25 629 687 962 540 ÷ 2 = 12 814 843 981 270 + 0;
  • 12 814 843 981 270 ÷ 2 = 6 407 421 990 635 + 0;
  • 6 407 421 990 635 ÷ 2 = 3 203 710 995 317 + 1;
  • 3 203 710 995 317 ÷ 2 = 1 601 855 497 658 + 1;
  • 1 601 855 497 658 ÷ 2 = 800 927 748 829 + 0;
  • 800 927 748 829 ÷ 2 = 400 463 874 414 + 1;
  • 400 463 874 414 ÷ 2 = 200 231 937 207 + 0;
  • 200 231 937 207 ÷ 2 = 100 115 968 603 + 1;
  • 100 115 968 603 ÷ 2 = 50 057 984 301 + 1;
  • 50 057 984 301 ÷ 2 = 25 028 992 150 + 1;
  • 25 028 992 150 ÷ 2 = 12 514 496 075 + 0;
  • 12 514 496 075 ÷ 2 = 6 257 248 037 + 1;
  • 6 257 248 037 ÷ 2 = 3 128 624 018 + 1;
  • 3 128 624 018 ÷ 2 = 1 564 312 009 + 0;
  • 1 564 312 009 ÷ 2 = 782 156 004 + 1;
  • 782 156 004 ÷ 2 = 391 078 002 + 0;
  • 391 078 002 ÷ 2 = 195 539 001 + 0;
  • 195 539 001 ÷ 2 = 97 769 500 + 1;
  • 97 769 500 ÷ 2 = 48 884 750 + 0;
  • 48 884 750 ÷ 2 = 24 442 375 + 0;
  • 24 442 375 ÷ 2 = 12 221 187 + 1;
  • 12 221 187 ÷ 2 = 6 110 593 + 1;
  • 6 110 593 ÷ 2 = 3 055 296 + 1;
  • 3 055 296 ÷ 2 = 1 527 648 + 0;
  • 1 527 648 ÷ 2 = 763 824 + 0;
  • 763 824 ÷ 2 = 381 912 + 0;
  • 381 912 ÷ 2 = 190 956 + 0;
  • 190 956 ÷ 2 = 95 478 + 0;
  • 95 478 ÷ 2 = 47 739 + 0;
  • 47 739 ÷ 2 = 23 869 + 1;
  • 23 869 ÷ 2 = 11 934 + 1;
  • 11 934 ÷ 2 = 5 967 + 0;
  • 5 967 ÷ 2 = 2 983 + 1;
  • 2 983 ÷ 2 = 1 491 + 1;
  • 1 491 ÷ 2 = 745 + 1;
  • 745 ÷ 2 = 372 + 1;
  • 372 ÷ 2 = 186 + 0;
  • 186 ÷ 2 = 93 + 0;
  • 93 ÷ 2 = 46 + 1;
  • 46 ÷ 2 = 23 + 0;
  • 23 ÷ 2 = 11 + 1;
  • 11 ÷ 2 = 5 + 1;
  • 5 ÷ 2 = 2 + 1;
  • 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.

410 075 007 400 646(10) = 1 0111 0100 1111 0110 0000 0111 0010 0101 1011 1010 1100 0110(2)

3. Determine the signed binary number bit length:

  • The base 2 number's actual length, in bits: 49.

  • 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, 49,

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.


Decimal Number 410 075 007 400 646(10) converted to signed binary in two's complement representation:

410 075 007 400 646(10) = 0000 0000 0000 0001 0111 0100 1111 0110 0000 0111 0010 0101 1011 1010 1100 0110

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