29 bytes would be half a kibibyte. 230 (= 1,0243 for how the units are divided) bytes is a gibibyte, and 109 bytes is a gigabyte. I use these when I feel I need to be unambiguous, but most of the time I'll use "gigabyte" for either. I wouldn't define it as 1,024,000,000 in any case, as that would be 1,024 megabytes as opposed to mebibytes, mixing SI and binary prefixes;106×210 bytes.
EDIT: parenthetical statement placed next to wrong number. Oops for math.