If a is a whole number such that `a+a=a`, then `a=`?

Does there exist a whole number a such that a-:a=a ?

Does there exist a whole number a such that a-:a=a?

Property 1 If a and b are two numbers such that a > b or a = b then a - b is a whole number. If a < b then subtraction a - b is not possible in whole numbers.

Assertion : If a is a whole number, then a+0=0+a=a . Reason : If a and b are whole numbers, then a+b is also a whole number.

The smallest whole number is

Property 7 (DIvision Algorithm) If a whole number a is divided by a non-zero whole number b then there exists whole numbers q and r such that a = bq + r whole either r = 0 or r < b .

Which is greates whole number?