What nineteen actually means across traditions
Nineteen is the cleanest example on the site of one real astronomical fact anchoring several independent traditions — and of a modern claim that attaches itself to that fact without inheriting its rigour.
This page collects every attestation of 19 documented on this site — 6 entries drawn from 5 traditions — each with the source you would use to check it and the evidence grade it carries. The table is generated directly from the published dataset, so it cannot disagree with it.
Attestations of 19
Sorted by tradition. A grade of verified means the tradition demonstrably says this — not that the claim is true about the world.
| Tradition | Attestation | Grade | Where to check it | Full discussion |
|---|---|---|---|---|
| Astronomy | The Metonic cycle: 19 tropical years ≈ 235 synodic months, the two differing by roughly two hours | verified | computation from modern values | page |
| Bahá’í | The Badíʿ calendar has 19 months of 19 days, plus intercalary days | verified | Kitáb-i-Aqdas; Badíʿ calendar | page |
| Cross-cultural | Metonic cycle: 235 lunations ≈ 19 tropical years | verified | Standard astronomy | page |
| Hebrew Bible | The fixed Hebrew calendar intercalates 7 leap months in each 19-year cycle | verified | fixed calendar rules, post-Hillel II | page |
| Quran | "Over it are nineteen" (74:30) is a textual fact about the verse | verified | Quran 74:30 | page |
| Quran | The "Code 19" system requires excluding 9:128–129 and making specific counting choices; mainstream scholarship rejects it and the required textual surgery is itself the objection | disputed | see the Code 19 analysis | page |
Mathematical properties of 19
Computed, not asserted. These are the properties any numerological reading has to work with, and often the ones that explain a number’s practical popularity.
| Property | Value |
|---|---|
| Prime factorisation | 19 (prime) |
| Divisors | 2 — 1, 19 |
| Sum of proper divisors | 1 — deficient |
| Digit sum / digital root | 10 / 1 |
What the evidence supports
disputed — overall assessment
The Metonic relation is exact enough to be useful and is the reason 19 appears in calendar systems: 19 tropical years and 235 synodic months differ by about two hours. The Hebrew calendar’s seven leap months per 19-year cycle follow directly. The Bahá’í 19×19 structure is different in kind — a designed system whose tradition states its own intent, which makes it verifiable rather than speculative. "Code 19" belongs to neither category: it requires excluding two verses of the Quran to work, and a system that needs the text altered to fit is not evidence about the text.
Try the number directly in the number lookup, or filter the full dataset in the comparison matrix.
Other number hubs
Every number in the corpus, including those without a hub page, is queryable in the number lookup.
Number Lookup
Query any integer and get its attestations and computed mathematical properties.
Comparison Matrix
The whole dataset as a filterable grid — tradition, number, meaning and grade.
Testing the Patterns
How these grades are assigned, and why a recurring number is weaker evidence than it looks.
Sacred Numbers
The comparative essays behind these hub tables.
Cite this page
Formatted references for this page. The evidence grade is part of the claim — when quoting a graded statement, carry the grade with it.