1845
1845 is the year the Great Famine began in Ireland.
- Odd
- Composite
Where 1845 fits
Why 1845 is special
Potato blight destroyed the crop, and about a million people died while Ireland continued exporting food under armed guard. The population fell by roughly a quarter through death and emigration, and has never returned to its pre-famine level.
Factors & digit properties
- Divisors (12)
- 1, 3, 5, 9, 15, 41, 45, 123, 205, 369, 615, 1845
- Prime factorisation
- 3^2 × 5 × 41
- Digit sum
- 18
- Digital root
- 9
Representations
- Decimal
- 1845
- Binary
- 11100110101
- Octal
- 3465
- Hexadecimal
- 735
- Roman numeral
- MDCCCXLV
- Scientific notation
- 1.845 × 10^3
Other mathematical patterns
- Deficient number
Related numbers & connections
Famine in Ireland and the Great Exhibition in London ran within six years of each other in the same state, which is a fact about distribution rather than about capability.
View 1851 →The Bengal famine of 1943 and the Irish famine from 1845 both occurred under British administration with food being exported during the deaths. Responsibility in both cases remains actively contested.
View 1943 →History
Potato blight destroyed the crop from 1845 and about a million people died while Ireland continued to export food under armed guard. Death and emigration cut the population by roughly a quarter, and it has never returned to its pre-famine level.
DocumentedHistoryGeography: IrelandPeriod: 1845–1852
Common questions
Is 1845 a prime number?
No, 1845 is not prime.
What are the factors of 1845?
The factors of 1845 are 1, 3, 5, 9, 15, 41, 45, 123, 205, 369, 615, 1845.
What is 1845 in Roman numerals?
1845 in Roman numerals is MDCCCXLV.
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