1676
1676 is the year the speed of light was first measured.
- Even
- Composite
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.
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
- Binary
- 11010001100
- Octal
- 3214
- Hexadecimal
- 68c
- Roman numeral
- MDCLXXVI
- Scientific notation
- 1.676 × 10^3
Other mathematical patterns
- Deficient number
Science
Rømer 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: 1 reviewer-confirmed record, sourced and reviewed before publication.
Last reviewed: 3 August 2026