There are infinite whole numbers IF you allow things like googols. If not, there are 999 trillion, 999 billion, 999 million, 999 thousand 9 hundred and 99 whole numbers. read more
Therefore,except zero all the whole nos. are natural numbers. Properties of Whole nos. : 1) The smallest natural number is 1. 2) The number 0 is the first and the smallest whole nos. 3) There are infinitely many or uncountable number of whole-numbers. 4) All natural numbers are whole-numbers. 5) All whole-numbers are not natural numbers. read more
To the nearest unit: none (other than itself) To the nearest 5: 5 (incl itself) To the nearest 10: 10 (incl itself) To the nearest n: n, where n is any integer. read more