1543
1543 is the year Copernicus published his heliocentric model.
- Odd
- Prime
Where 1543 fits
Why 1543 is special
He delayed publication for decades and reportedly saw the printed book on the day he died. The model was not immediately more accurate than the Earth-centred one it challenged, because Copernicus kept circular orbits — Kepler's ellipses supplied the accuracy sixty years later.
Same number, different meanings
How 1543 is understood across different contexts — never implying one meaning because of another.
- Mathematics
He delayed publication for decades and reportedly saw the printed book on the day he died. The model was not immediately more accurate than the Earth-centred one it challenged, because Copernicus kept circular orbits — Kepler's ellipses supplied the accuracy sixty years later.
- History
In 1543, Copernicus's De revolutionibus set out the heliocentric model, and Vesalius's De humani corporis fabrica reformed anatomy (Europe).
- Science
Copernicus put the Sun at the centre but kept circular orbits, so his model was no better at predicting positions than the Earth-centred one it challenged. Kepler's ellipses supplied the accuracy sixty years later, which is why the revolution took longer than the publication date suggests.
1543 is part of
Factors & digit properties
- Divisors (2)
- 1, 1543
- Prime factorisation
- 1543
- Digit sum
- 13
- Digital root
- 4
Representations
- Decimal
- 1543
- Scientific notation
- 1.543 × 10^3
Roman numerals
M D X L I I I
MDXLIII uses the subtractive pair XL: ten before fifty — fifty minus ten.
Binary
1 1 0 0 0 0 0 0 1 1 1
1 × 1,024 + 1 × 512 + 0 × 256 + 0 × 128 + 0 × 64 + 0 × 32 + 0 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 1 × 1 = 1,543
Octal
3 0 0 7
3 × 512 + 0 × 64 + 0 × 8 + 7 × 1 = 1,543
Hexadecimal
6 0 7
6 × 256 + 0 × 16 + 7 × 1 = 1,543
Read as powers of two: 1,024 + 512 + 4 + 2 + 1 = 1,543.
In historical numeral systems
Egyptian
1 lotus, 5 coils of rope, 4 hobbles, 3 strokes
1 × 1,000 + 5 × 100 + 4 × 10 + 3 × 1 = 1,543. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 5 vertical wedges (sixties place), 4 corner wedges + 3 vertical wedges (units place)
25 × 60 + 43 = 1543. Places are separated by a space on the tablet, with the higher place written first.
Systems that simply cannot reach this value are left out. Where a script needs a font most readers do not have, the reading is given instead of the glyphs — see number systems for each system in full.
Other mathematical patterns
- Deficient number
- Lucky number (mathematical sieve)
Related numbers & connections
1543 is a year in the 16th century, in the 1540s.
Copernicus moved the Sun to the centre and Newton explained why the arrangement holds. The 144 years between them include Kepler's ellipses, which supplied the accuracy Copernicus lacked.
View 1687 →History
In 1543, Copernicus's De revolutionibus set out the heliocentric model, and Vesalius's De humani corporis fabrica reformed anatomy (Europe).
DocumentedHistoryGeography: EuropePeriod: 1543
Science
Copernicus put the Sun at the centre but kept circular orbits, so his model was no better at predicting positions than the Earth-centred one it challenged. Kepler's ellipses supplied the accuracy sixty years later, which is why the revolution took longer than the publication date suggests.
DocumentedSciencePeriod: 1543
Common questions
Is 1543 a prime number?
Yes, 1543 is prime — it has exactly two positive divisors: 1 and itself.
What are the factors of 1543?
The factors of 1543 are 1, 1543.
What is 1543 in Roman numerals?
1543 in Roman numerals is MDXLIII. XL is subtractive: ten before fifty — fifty minus ten. Written additively it would be MDXXXXIII, which Roman inscriptions used freely — the strict subtractive form is a later convention.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 2 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026