Timekeeping in "Embassytown"

Non-Terre-centric measurement in science fiction is surprisingly uncommon, but China Miéville's "Embassytown" does an interesting job of it. Rather than seconds or local days or years, time is measured with hours according to the metric system prefixes. The base SI unit is not the hour but the second, of course, but this is similar to using the kilogram as basic rather than the gram.

We should assume an hour is 3,600 contemporary Terre seconds.Thus, a kilohour is just more than 41 days (comparable to a month), a megahour is about 114 Julian years, and a gigahour is about 114,077 Julian years.

This is relatively human-scale, perhaps even compared to the kilosecond, but again there's the difficulty of nothing in between the kilo- and the mega- and the giga-. Here there's no basic unit in between the near-month and the near-century. I suspect that humans need to measure human-scale time with a unit that has more factors than 1, 2, 5, and 10.