1220
1220 is a year in the 13th century. Salisbury Cathedral was begun on a new site and completed in a single style within thirty-eight years (England).
- Even
- Composite
Where 1220 fits
Why 1220 is special
1220 has a profile because of what happened in it rather than because of any property of the number: Salisbury Cathedral was begun on a new site and completed in a single style within thirty-eight years (England).
1220 is part of
Factors & digit properties
- Divisors (12)
- 1, 2, 4, 5, 10, 20, 61, 122, 244, 305, 610, 1220
- Prime factorisation
- 2^2 × 5 × 61
- Digit sum
- 5
- Digital root
- 5
Representations
- Decimal
- 1220
- Scientific notation
- 1.220 × 10^3
Roman numerals
M C C X X
Binary
1 0 0 1 1 0 0 0 1 0 0
1 × 1,024 + 0 × 512 + 0 × 256 + 1 × 128 + 1 × 64 + 0 × 32 + 0 × 16 + 0 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 1,220
Octal
2 3 0 4
2 × 512 + 3 × 64 + 0 × 8 + 4 × 1 = 1,220
Hexadecimal
4 c 4
4 × 256 + c × 16 + 4 × 1 = 1,220
Read as powers of two: 1,024 + 128 + 64 + 4 = 1,220.
In historical numeral systems
Egyptian
1 lotus, 2 coils of rope, 2 hobbles
1 × 1,000 + 2 × 100 + 2 × 10 = 1,220. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
2 corner wedges (sixties place), 2 corner wedges (units place)
20 × 60 + 20 = 1220. 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
- Abundant number
- Harshad (Niven) number
Related numbers & connections
1220 is a year in the 13th century, in the 1220s.
Numbers Around Us
- appears inHistorical years
why?
Strength 0.50, confidence "high".
History
In 1220, Salisbury Cathedral was begun on a new site and completed in a single style within thirty-eight years (England).
DocumentedHistoryGeography: EnglandPeriod: 1220
Common questions
Is 1220 a prime number?
No, 1220 is not prime.
What are the factors of 1220?
The factors of 1220 are 1, 2, 4, 5, 10, 20, 61, 122, 244, 305, 610, 1220.
What is 1220 in Roman numerals?
1220 in Roman numerals is MCCXX.
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: 15 July 2026