Having researched many different perspectives on the meaning of numbers, I take the best of what I see from the apparently contradictory views and discard the rest. All the while I am true to the intuitive psychic sense that just knows the meaning, without external reference of any kind. The following is a brief outline delineating numeric meanings in this writer's experience and understanding:
0 - Zero, Origin, Source, Emptiness, Clear Light, Infinite Eternal Essence
1 - One, Energy, Unity/Being, Presence, Life and Light, Core, Ether, Fire, Solar
2 - Two, Matter/Substance, Duality, Being HERE, Existence and Polarity, Earth, Water, Lunar
3 - Three, Mind, Harmony, The Moment, Activity, Experience, Cognition, Perspective, Active Intelligence, Earth, Air, Mercury, Venus, Jupiter
4 - Four, Physical Matter, Harmony thru Conflict, The Environment, Home & Hearth, Family, Workplace, Confining Places, Earth, Water, Moon, Venus, Saturn
5 - Five, Self Expression, Creative Will, Intention made Manifest, Joy and Pleasure, Recreational/Open Places, Selfish (but most essential) Love Interests, Idealism & Individual Purpose, Solar Fire, Mars, Mercury, Sun
6 - Six, Discipline, Devotion, Practice, Work, Cleanliness, Harmony, Service, Helpfulness, Practicality, Getting things Done, Purpose Implementation, Completion of 3rd Dimension (space), Earth & Venus, Ceres & Vesta, Mercury & Saturn
7 - Seven, Divine Connection, Global Unity, Wisdom & Guidance of Angels, Vibration & Attraction, Karmic Justice, Relationship, Other(s), Cooperation and Coexistence
8 - Eight, Divine Ascension, Infinite, Greatness, Evolution, Polarity (Material & Spiritual worlds), Transformation, Change and Growth, All Elements, Mars & Pluto, Saturn & Chiron.
9 - Nine, Divine Actualization, Liberated Potential, Generosity and Goodwill, Walking the Walk, One-Pointed Concentration (developed at 8), Higher Purpose, Optimism, Teaching/Counseling Others, Fire, Mars, Uranus & Pluto
10 - Ten, Cosmic Realization, The Religious Man (spiritual not orthodox), Dharma, Beyond the Self, Blueprint of Perfection, Rebirth in Spirit, Contribution to Humanity, Completion of 4th Dimension (Time), Sun, Jupiter & Pluto, Solar Self Mastery
11 - Eleven, Higher Self Realization, Stars, Vibrations, Astrological & Occult Influence/Understanding, Omniscience, Cosmic Consciousness, The other 'One'
Ruler is Uranus, God of the Sky and the observable Cosmos.
12 - Twelve, Ultimate Liberation, Nirvana, Peace, Love & Understanding, Universality, Divine Love, Impersonal Self or Soul, Meditation, Wisdom and Bliss, Omnipresence. Ruler is Neptune, God of the Ocean and the Heavens.
13 - Thirteen, Negation, Nihilism, Elimination, Involution, Rising Above Limitation, Indomitable Soul Power, Positive Destruction, Ending Superstition, "Black Teachers", Death, Rebirth and Regeneration. Ruler is Pluto, God of the Underworld and the Seed of Life.
14 - Fourteen, Affirmation & Visualization, Angels & Archangels, "White Teachers", Restoration of Faith and putting Essential Values to the test, practicing temperance and moderation, avoiding excess and distraction to remain firmly rooted on the Path.
Rulers are Jupiter (#10) and Neptune (#12)
15 - Fifteen, Integration of Spiritual and Material, Self Sufficiency, Responsibility and Full Functionality, Maturity (developed at #'s 13 & 14), Completion of 5th Dimension (Life)
16 - Rebirth in the Fire of Divine Will - "The Tower"
17 - Guidance and Faith in the Cosmos - "The Star"
18 - Mind, Imagination & Deception, Maya - "The Moon"
19 - Individualism, Autonomy & Self-Sufficiency - "The Sun"
20 - Duality & The Battle of Good versus Evil - "Judgment"
21 - Perfection, Paradise, Completion of 6th Dimension - "The World"
Numbers 13, 14, 16 & 19 are considered to be "Karmic Debt" numbers.
Number 13 works to remove all dead weight and inessentials from the existence. Number 14 challenge is to not get caught up in diversions or excess while in the process of expanding horizons. Number 16 destroys the previous structure of our personal existence so that a higher order can be created anew. Number 19 must come to grips with the illusion of total autonomy, swallow pride and occasionally ask others for help. I personally would add the Number 18 to this list, as there is no greater human karmic challenge/obstacle than the ordinary lunar mind (Maya) itself.