TI-BASIC, <s>20 17 16</s> 13
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<s>Because it is tokenized, TI-BASIC is often competitive at simple math challenges, but not this one since there is no "divisible" command.</s> Maybe it is after all, but this is still longer than CJam and Pyth.

This uses David Hammond's method.

    not(fPart(Ans/4/4^not(fPart(sub(Ans

Old code at 16 bytes:

    not(fPart(Ans/16not(fPart(sub(Ansnot(fPart(Ans/4
    
Ungolfed:

    not(fPart(Ans/16) and not(fPart(Ans/100) and not(fPart(Ans/4))))

`fPart(` is "fractional part"; exponentiation has higher precedence than division. In TI-BASIC, close-parens are optional.

I use undocumented behavior of the `sub(` command, usually used to get a substring: when its argument is a number instead of a string, it divides the number by 100. It will work on a TI-83 or 84 series calculator.

20 -> 17 by rearranging code to allow removal of close-parens; 17 -> 16 by replacing 400 with 16; 16 -> 13 by using David Hammond's idea.