4

← 3 4 5 →
−1 0 1 2 3 4 5 6 7 8 9 →
Cardinalfour
Ordinal4th
(fourth)
Numeral systemquaternary
Factorization22
Divisors1, 2, 4
Greek numeralΔ´
Roman numeral
Greek prefixtetra-
Latin prefixquadri-/quadr-
Binary1002
Ternary113
Senary46
Octal48
Duodecimal412
Hexadecimal416
ArmenianԴ
Arabic, Kurdish٤
Persian, Sindhi۴
Shahmukhi, Urdu۴
Ge'ez፬
Bengali, Assamese৪
Chinese numeral四,亖,肆
Devanagari४
Santali᱔
Telugu౪
Malayalam൪
Tamil௪
Hebrewד
Khmer៤
Thai๔
Kannada೪
Burmese၄
Babylonian numeral𒐘
Egyptian hieroglyph, Chinese counting rod||||
Maya numerals••••
Morse code.... _
Preview warning: Page using Template:Infobox number with unknown parameter "multiple+up+to+4+times"
Two modern handwritten fours

4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures.