|A diagram (Ѻ) showing the atoms and Atum hypothesis, namely that Leucippus, after studying in Egypt, based the word "atom" on the Egyptian god Atum, the one who called for the first land mound from the watery void or vacuum.|
In 580BC, Thales, among Greek philosophers, initiated the study abroad in Egypt method of education. Although little is known about Leucippus, the supposed coiner of the term “atomos”, we do know that his student Democritus did study in Egypt (Pliny, c.77AD) (Ѻ), for up to seven years (Ѻ), according to some accounts.  Accordingly, Democritus, speculatively speaking, would have learned at least the following basic religio-mythology cosmologies, and therein thematically have gotten the idea of first earth or "Atum" arising out of or existing in the void aspects of the Ogdoad, the gods Huh (space) and Hauhet (infinity) specifically:
0. Pre-Dynastic creation myth | 3500BC | Supreme god: Horus
1. Heliopolis creation myth | 3100BC | Supreme god: Atum [Atom] or Atum-Ra / Ennead
2. Memphis creation myth | 2800BC | Supreme god: Ptah3. Hermopolis creation myth | 2400 BC | Supreme god: Ogdoad [Void]4. Thebian creation myth | 2050 BC | Supreme god: Amen5. Amarnan creation myth | 1300BC | Supreme god: Aten6. Saite recension | 670BC | Book of Dead (canonized)
The following are the extant fragments of Democritus, wherein the term "atom" is used, according to which, in a very conjectural manner, it could be possible that while dismissing the concept of gods from his model, he may have kept the idea of matter (Atum) and void (Huh) as his basic model; or this was Leucippus’ basic model (but fragments from him are lacking), and he but expanded on it in secular/scientific themed terms:
“It has often been demonstrated that we do not grasp how each thing is or is not. Sweet exists by convention, bitter by convention, color by convention. Atoms and void alone exist in reality. . . We know nothing accurately in reality, but only as it changes according to the bodily condition, and the constitution of those things that flow upon the body and impinge upon it. It will be obvious that it is impossible to understand how in reality each thing is.”— Democritus (c.420BC), Pay (Ѻ) fragment #26
“The universe is infinite because it has not been produced by a creator. The causes of what now exists had no beginning.”— Democritus (c.420BC), Pay (Ѻ) fragment #45
“The material cause of all things that exist is the coming together of atoms and void. Atoms are too small to be perceived by the senses. They are eternal and have many different shapes, and they can cluster together to create things that are perceivable. Differences in shape, arrangement, and position of atoms produce different things. By aggregation they provide bulky objects that we can perceive with our sight and other senses.”— Democritus (c.420BC), Pay (Ѻ) fragment #47
“We see changes in things because of the rearrangement of atoms, but atoms themselves are eternal. Words such as ‘nothing’, ‘the void’, and ‘the infinite’ describe space. Individual atoms are describable as ‘not nothing’, ‘being’, and ‘the compact’. There is no void in atoms, so they cannot be divided. I hold the same view as Leucippus regarding atoms and space: atoms are always in motion in space.”— Democritus (c.420BC), Pay (Ѻ) fragment #48
“Nothing exists except atoms and empty space; everything else is opinion.”— Democritus (c.420BC), Pay (Ѻ) fragment #49
In 1954, George James, in his Stolen Legacy, a book which argues that Greek philosophy originated in ancient Egypt, Memphite theology (see: Memphis creation myth) specifically, suggested that the Greek term “atom” is based on the name of the Egyptian god Atum.  Others such as Martin Bernal (1987) and Anthony Preus (1993) and others have published views forwarding this argument. 
Atum | Atom | Adam
See main: Atum, Atom, AdamIn 1949, Rene Lubicz, in his The Temple of Man, connected the Egyptian Atum to the Greek biblical Adam, and on this connection.
In 2001, Edward Smith, in his David’s Questions, based on Lubicz, was speculating about the etymological relation between all three:
“Surely there must be an archetypal relationship between Adam (hard) and atom (indivisible) from which these two Greek sources arose?”
— Edward Smith (2001), David’s Question (pg. #)
The following are related quotes:
“Small wonder Leucippus and Democritus jointly held the view that Atom (Atum) was the basic principle of the universe.”— Boniface Nwigwe (2004), Emergent and Contentious Issues in African Philosophy (pg. 138)
1. James, George. (1954). Stolen Legacy (Ѻ)(Ѻ). Publisher.
2. Lefkowitz, M. (1998). Not Out of Africa (§149: Atoms and Atum, pg. 253-). Publisher.
3. Thims, Libb. (2018). Human Chemical Thermodynamics – Chemical Thermodynamics Applied to the Humanities: Sociology, Economics, History, Philosophy, Ethics, Government, Politics, and Business (pdf). Publisher.