222
+222 is the international calling code for Mauritania.
- Even
- Composite
Where 222 fits
Why 222 is special
Mauritania was the last country in the world to abolish slavery in law, in 1981, and did not criminalise it until 2007.
Same number, different meanings
How 222 is understood across different contexts — never implying one meaning because of another.
- Mathematics
Mauritania was the last country in the world to abolish slavery in law, in 1981, and did not criminalise it until 2007.
- Science
Radon-222 is a decay product of radium in soil and rock. It is a leading cause of lung cancer after smoking in several countries, which is why building codes in affected areas require mitigation.
- Geography
+222 reaches Mauritania, which abolished slavery legally in 1981 — later than any other state — and made it a prosecutable crime only in 2007.
222 is part of
Factors & digit properties
- Divisors (8)
- 1, 2, 3, 6, 37, 74, 111, 222
- Prime factorisation
- 2 × 3 × 37
- Digit sum
- 6
- Digital root
- 6
Representations
- Decimal
- 222
- Scientific notation
- 2.220 × 10^2
Roman numerals
C C X X I I
Binary
1 1 0 1 1 1 1 0
1 × 128 + 1 × 64 + 0 × 32 + 1 × 16 + 1 × 8 + 1 × 4 + 1 × 2 + 0 × 1 = 222
Octal
3 3 6
3 × 64 + 3 × 8 + 6 × 1 = 222
Hexadecimal
d e
d × 16 + e × 1 = 222
Read as powers of two: 128 + 64 + 16 + 8 + 4 + 2 = 222.
In historical numeral systems
Egyptian
2 coils of rope, 2 hobbles, 2 strokes
2 × 100 + 2 × 10 + 2 × 1 = 222. The signs are simply repeated and added; where they sit on the line is a matter of layout, not value.
Babylonian
3 vertical wedges (sixties place), 4 corner wedges + 2 vertical wedges (units place)
3 × 60 + 42 = 222. Places are separated by a space on the tablet, with the higher place written first.
Greek (Ionic)
sigma, then kappa, then beta, marked as a numeral
sigma-kappa-beta + keraia
sigma + kappa + beta 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 kaf, then bet
resh-kaf-bet
resh (200) + kaf (20) + bet (2) = 222, written in descending order.
Maya
2 bars + 1 dot (upper, twenties place) over 2 dots (lower, units place)
11 × 20 + 2 = 222. 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
- Palindromic number
- Abundant number
- Repdigit
- Harshad (Niven) number
Related numbers & connections
Mauritania and Mali share a long Saharan border. Mauritania was the last country in the world to criminalise slavery, in 2007.
View 223 →Nearby in a sequence
- is adjacent to223
why?
Strength 0.50, confidence "high".
Science
Radon-222 is a decay product of radium in soil and rock. It is a leading cause of lung cancer after smoking in several countries, which is why building codes in affected areas require mitigation.
DocumentedScienceGeography: GlobalPeriod: 1900–
Geography
+222 reaches Mauritania, which abolished slavery legally in 1981 — later than any other state — and made it a prosecutable crime only in 2007.
DocumentedGeographyGeography: Mauritania
Common questions
Is 222 a prime number?
No, 222 is not prime.
What are the factors of 222?
The factors of 222 are 1, 2, 3, 6, 37, 74, 111, 222.
What is 222 in Roman numerals?
222 in Roman numerals is CCXXII.
About this page's data
Mathematical facts:computed directly from the number's value — nothing to source or verify externally.
Contextual records: 2 reviewer-confirmed records, sourced and reviewed before publication.
Last reviewed: 15 July 2026