1678
1678 is the year Huygens proposed the wave theory of light.
- Even
- Composite
Where 1678 fits
Why 1678 is special
It was overshadowed by Newton's particle account for a century until interference experiments settled the matter, and then quantum mechanics made both partly right.
Factors & digit properties
- Divisors (4)
- 1, 2, 839, 1678
- Prime factorisation
- 2 × 839
- Digit sum
- 22
- Digital root
- 4
Representations
- Decimal
- 1678
- Binary
- 11010001110
- Octal
- 3216
- Hexadecimal
- 68e
- Roman numeral
- MDCLXXVIII
- Scientific notation
- 1.678 × 10^3
Other mathematical patterns
- Deficient number
- Semiprime
Science
Huygens's wave account of 1678 lost to Newton's corpuscles for a century, was vindicated by interference experiments around 1800, and was then absorbed into a quantum description where neither picture is complete.
DocumentedScienceGeography: NetherlandsPeriod: 1678
Common questions
Is 1678 a prime number?
No, 1678 is not prime.
What are the factors of 1678?
The factors of 1678 are 1, 2, 839, 1678.
What is 1678 in Roman numerals?
1678 in Roman numerals is MDCLXXVIII.
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