Here, Isaiah comforted Israel by reminding them that their God created the heavens and did so much like a general would line up his troops for war.
From Strong's Exhaustive Concordance of the Bible, The Hebrew word for "number" used here is "miçpâr," an arithmetical term for number or enumeration.
Regarding the term "hosts," Albert Barnes notes: "The word here alludes to the fact that the heavenly bodies seem to be marshalled, or regularly arrayed as an array; that they keep their place, preserve their order, and are apparently led on from the east to the west, like a vast army under a mighty leader…" (Barnes et al., 2005)
Merriam Webster's Collegiate Dictionary defines the noun form of
the word "array" as "a number of mathematical elements arranged in rows and columns."
Therefore, according to the prophet Isaiah, the application of an array of numbers to the Genesis creation account is not artificial. Additionally, four verses earlier, the prophet writes in Isaiah 40:22: "It is he that sits on the circle of the earth, and the inhabitants thereof are as grasshoppers; that stretches out the heavens as a curtain, and spreads them out as a tent to dwell in:"
Many readers mistake this term "circle of the Earth" as evidence of the Bible's foretelling that Earth is round, but "circle" in this passage is the same Hebrew word translated "compass" in Prov 8:27 and "circuit" in Job 22:14.
It implies that this Hebrew word "chûg" in Creation's context is more descriptive of the Earth's orbit and spin, rather than its shape (Herbert and Johnson, 2018).
This Biblical evidence gives weight and credibility to our mathematical idea of six days being six rotations / logarithmic." DereklMarshall
