1676
1676 is the year the speed of light was first measured.
- Even
- Composite
Where 1676 fits
Why 1676 is special
Ole Rømer noticed that eclipses of Jupiter's moons ran late when Earth was further away, and deduced that light takes time to travel. The measurement was about 26 percent low and the principle was right.
1676 is part of
Factors & digit properties
- Divisors (6)
- 1, 2, 4, 419, 838, 1676
- Prime factorisation
- 2^2 × 419
- Digit sum
- 20
- Digital root
- 2
Representations
- Decimal
- 1676
- Scientific notation
- 1.676 × 10^3
Roman numerals
M D C L X X V I
Binary
1 1 0 1 0 0 0 1 1 0 0
1 × 1,024 + 1 × 512 + 0 × 256 + 1 × 128 + 0 × 64 + 0 × 32 + 0 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 1,676
Octal
3 2 1 4
3 × 512 + 2 × 64 + 1 × 8 + 4 × 1 = 1,676
Hexadecimal
6 8 c
6 × 256 + 8 × 16 + c × 1 = 1,676
Read as powers of two: 1,024 + 512 + 128 + 8 + 4 = 1,676.
In historical numeral systems
Egyptian
1 lotus, 6 coils of rope, 7 hobbles, 6 strokes
1 × 1,000 + 6 × 100 + 7 × 10 + 6 × 1 = 1,676. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges + 7 vertical wedges (sixties place), 5 corner wedges + 6 vertical wedges (units place)
27 × 60 + 56 = 1676. 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
Related numbers & connections
1676 is a year in the 17th century, in the 1670s.
Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
Science
In 1676, Ole Rømer produced the first quantitative estimate of the speed of light (Denmark).
DocumentedScienceGeography: DenmarkPeriod: 1676Rømer explained discrepancies in the timing of Jupiter's moon eclipses by proposing that light travels at finite speed. His figure was roughly a quarter too low, and the conclusion that light is not instantaneous was the significant part.
DocumentedSciencePeriod: 1676
Common questions
Is 1676 a prime number?
No, 1676 is not prime.
What are the factors of 1676?
The factors of 1676 are 1, 2, 4, 419, 838, 1676.
What is 1676 in Roman numerals?
1676 in Roman numerals is MDCLXXVI.
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