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'ez
Bengali, Assamese
Chinese numeral四,亖,肆
Devanagari
Telugu
Malayalam
Tamil
Hebrewד
Khmer
Thai
Kannada
Burmese
Babylonian numeral𒐘
Egyptian hieroglyph, Chinese counting rod||||
Maya numerals••••
Morse code.... _

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.