1 is the Natural number which is the smallest Odd number.
100 is the smallest 3-digit natural number.
Least or smallest natural number is 1.
The natural numbers are the numbers used to count things (the counting numbers). The smallest number of things you can have when you have some to count is one. Thus the smallest natural number is 1.
The smallest multiple of a natural number n, is 1xn, or the number itself. We do not count 0xn which of course would be zero for every natural number n.
It is 10.