247
+247 is the international calling code for Ascension Island.
- Odd
- Composite
Where 247 fits
Why 247 is special
Ascension has no indigenous population and no right of abode: everyone there is present under a work contract. It was made habitable by a deliberate nineteenth-century afforestation.
Same number, different meanings
How 247 is understood across different contexts — never implying one meaning because of another.
- Mathematics
Ascension has no indigenous population and no right of abode: everyone there is present under a work contract. It was made habitable by a deliberate nineteenth-century afforestation.
- Everyday life
24/7 denotes continuous availability, from twenty-four hours across seven days. The construction dates from American usage in the 1980s and spread with services that genuinely never close, such as call centres and online systems.
- Technology & computing
Continuous operation is quoted in service agreements as nines rather than as 24/7: 99.9 percent permits nearly nine hours of downtime a year, and 99.999 permits about five minutes. The slogan and the guarantee are different claims.
- Geography
+247 reaches Ascension Island, where nobody holds permanent residency rights and the cloud forest on its peak was planted deliberately from the 1840s to generate rainfall.
Factors & digit properties
- Divisors (4)
- 1, 13, 19, 247
- Prime factorisation
- 13 × 19
- Digit sum
- 13
- Digital root
- 4
Representations
- Decimal
- 247
- Scientific notation
- 2.470 × 10^2
Roman numerals
C C X L V I I
CCXLVII uses the subtractive pair XL: ten before fifty — fifty minus ten.
Binary
1 1 1 1 0 1 1 1
1 × 128 + 1 × 64 + 1 × 32 + 1 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 1 × 1 = 247
Octal
3 6 7
3 × 64 + 6 × 8 + 7 × 1 = 247
Hexadecimal
f 7
f × 16 + 7 × 1 = 247
Read as powers of two: 128 + 64 + 32 + 16 + 4 + 2 + 1 = 247.
In historical numeral systems
Egyptian
2 coils of rope, 4 hobbles, 7 strokes
2 × 100 + 4 × 10 + 7 × 1 = 247. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
4 vertical wedges (sixties place), 7 vertical wedges (units place)
4 × 60 + 7 = 247. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
sigma, then mu, then zeta, marked as a numeral
sigma-mu-zeta + keraia
sigma + mu + zeta written in descending order and added — the letters carry their values wherever they stand, so this is addition, not place value.
Hebrew numerals
resh, then mem, then zayin
resh-mem-zayin
resh (200) + mem (40) + zayin (7) = 247, written in descending order.
Maya
2 bars + 2 dots (upper, twenties place) over 1 bar + 2 dots (lower, units place)
12 × 20 + 7 = 247. Places stack vertically with the smallest at the bottom, so the upper group is worth twenty times the lower.
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
- Pentagonal number
- Semiprime
- Harshad (Niven) number
Related numbers & connections
24/7 is built from twenty-four hours across seven days, and denotes availability rather than a duration.
View 24 →Other connections
Everyday life
24/7 denotes continuous availability, from twenty-four hours across seven days. The construction dates from American usage in the 1980s and spread with services that genuinely never close, such as call centres and online systems.
DocumentedEveryday lifeGeography: Originating in United States EnglishPeriod: 1980s–
Technology & computing
Continuous operation is quoted in service agreements as nines rather than as 24/7: 99.9 percent permits nearly nine hours of downtime a year, and 99.999 permits about five minutes. The slogan and the guarantee are different claims.
DocumentedTechnology & computingGeography: GlobalPeriod: 1990s–
Geography
+247 reaches Ascension Island, where nobody holds permanent residency rights and the cloud forest on its peak was planted deliberately from the 1840s to generate rainfall.
DocumentedGeographyGeography: Ascension Island
Common questions
Is 247 a prime number?
No, 247 is not prime.
What are the factors of 247?
The factors of 247 are 1, 13, 19, 247.
What is 247 in Roman numerals?
247 in Roman numerals is CCXLVII. XL is subtractive: ten before fifty — fifty minus ten. Written additively it would be CCXXXXVII, which Roman inscriptions used freely — the strict subtractive form is a later convention.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 3 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026