Numbers hold meaning and value both metaphysically and in a more monetary sense. In ancient Egypt numbers held meaning and spiritual significance.
Pythagoras studied in ancient Egypt for nearly 20 years and brought back much of what he learned to the Western world. He has often been labeled as the one who defined numerology.
Ancient Egyptians had an extensive knowledge of numbers, math, and geometry. The massive pyramids attest to this fact. It was a symbolic civilization that assigned meaning to all of their symbols and most aspects of daily life.
But let's start with number one....
In ancient Egypt, one signified and symbolized "Atum". The first God to be worshipped. Atum was considered the father of the gods and the creator of the first divine couple- Shu and Tefnut. He was also held to be the father of all pharaohs and many ancient Egyptian pharaohs used the title, "Son of Atum".
TWO. Duality was a huge aspect of ancient Egyptian life. It pervades throughout the culture and it the heart of the ancient Egyptian concept of life and the universe. Light - Dark. Sun - Moon. This list is endless... It signifies the balance between to opposites and the union of those polar opposites in many instances. The representation of opposites that are interconnected... as in the sun and moon. While the sun and moon are significant in their duality, they are also interconnected and work in harmony.
THREE....
Three is considered heavenly as it represented the various godly trinities we find throughout ancient Egyptian history. It represented plurality. The Soul, Face, and Body of God. Examples include: Osiris - Isis and Horus .. and .. Amun, But, and Khonsua.
And there's also Orions Belt.... a significant group of three stars that line up with the pyramids at Giza. The stars were perfectly aligned with the pyramids in 10,000BC. Some might say the pyramids are as old as this.. mainstream archaeology discounts this theory but they really have little to no evidence to disprove it. (total side note).
FOUR.....When mummies were preserved the organs were extracted from the body. There were four jars that were used in this process. These four jars represented the four sons of Horus- protective deities. The human headed Imsety- guarded the liver. The baboon-headed god, Hapy protected the lungs. The falcon-headed Qebehsenuef guarded the intestines and the jackal-headed god, Duamutef protected the stomach.
The Egyptians symbolized 4 as the essence of physicality and earthiness due to the world being created of: air "Shu", moisture "Tefnut", sky "Nut" and earth "Geb".
The earliest use of number 4 is the puzzling presentation of honeybees and honeybee hieroglyphs with 4 legs.
FIVE.... Five represented the universe, where all of the gods lived eternally.
The second god, Rê, named five gods and goddesses. Thoth added five days to the year by winning the light from the moon in a game of gambling. It took five days for the five children of Nut and Geb to be born. Five is the number of balance. Five symbolizes man, health and love. It combines the female number two with the male number three. Egyptians also believed that the human spirit made up five parts - Ib, Sheut, Ren, Ba, Ka.
SIX...
The number 6 represents Thoth, the god of wisdom and learning.
SEVEN....
The number seven was apparently the Egyptian symbol of such ideas as perfection, effectiveness, and completeness. Seven thousand barrels of red beer were used to trick Sekhmet out of killing.
In ancient Egypt there were seven paths to heaven and seven heavenly cows; Osiris led his father through seven halls of the underworld.
EIGHT.... The Ogdoad were 8 deities that were worshipped in Hermopolis; they had animal heads and human bodies. There were four males with their 4 female counterparts. Nun and Naunet, Heh and Haunt, Ken and Kauket, and Amun and Amaunet.
NINE....
The number nine was a sacred and symbolic number that could also stand for 'all' gods. This was because the Egyptians indicated plurals by using three, and nine was thus perceived as the plural of plurals. The most important ennead was that of Heliopolis, often called the Great Ennead.
Sources:
https://journals.ekb.eg/article_67177_52136ca0ac7e3d2a26c345569d4bcbaa.pdf}
https://en.wikipedia.org/wiki/Numbers_in_Egyptian_mythology
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3291302/
https://www.metmuseum.org/art/collection/search/559935