4

Summary

4 is a positive integer^[1]. 4 ranks in the top 0.28% of positive_integer entities by monthly Wikipedia readership (8,150 views/month, #2 of 724).^[2]

Key Facts

• 4's instance of is recorded as positive integer^[3].
• 4's instance of is recorded as composite number^[4].
• 4's instance of is recorded as deficient number^[5].
• 4's instance of is recorded as square number^[6].
• 4's instance of is recorded as even number^[7].
• 4's instance of is recorded as centered triangular number^[8].
• 4's instance of is recorded as tetrahedral number^[9].
• 4's instance of is recorded as power of two^[10].
• 4's instance of is recorded as strictly non-palindromic number^[11].
• 4's instance of is recorded as harshad number^[12].
• 4's instance of is recorded as semiprime^[13].
• 4's instance of is recorded as trimorphic number^[14].
• 4's instance of is recorded as Motzkin number^[15].
• 4 followed 3^[16].
• 4 was followed by 5^[17].
• 4's Commons category is recorded as 4 (number)^[18].
• 4 is the opposite of −4^[19].
• 4 is the opposite of ¼^[20].
• 4's Unicode character is recorded as 4^[21].
• 4's Unicode character is recorded as ٤^[22].
• 4's Unicode character is recorded as ۴^[23].
• 4's Unicode character is recorded as Ⅳ^[24].
• 4's Unicode character is recorded as ⅳ^[25].
• 4's Unicode character is recorded as ④^[26].
• 4's Unicode character is recorded as ⑷^[27].

Body

Definition and Type

Recorded instance of include positive integer^[3], composite number^[4], deficient number^[5], square number^[6], even number^[7], and centered triangular number^[8]. Recorded opposite of include −4^[19] and ¼^[20].

Influence

Things named for 4 include Blue Ivy Carter^[28], a singer^[29], b. 2012^[30], of United States^[31]; Quaternary^[32], a system^[33]; Thursday^[34], a day of the week^[35]; Wednesday^[36], a day of the week^[37]; Four Knights Game^[38], a chess opening^[39]; FOUR^[40], a building complex^[41], in Germany^[42], founded in 2024^[43]; and Tylonycteris bat coronavirus HKU4^[44], a taxon^[45].

Why It Matters

4 ranks in the top 0.28% of positive_integer entities by monthly Wikipedia readership (8,150 views/month, #2 of 724).^[2] 4 has Wikipedia articles in 29 language editions, a strong signal of global cultural recognition.^[46] 4 is known by 49 alternative names across languages and contexts.^[47]

Entities named for 4 include Blue Ivy Carter^[28], a singer^[29], b. 2012^[30], of United States^[31]; Quaternary^[32], a system^[33]; Thursday^[34], a day of the week^[35]; Wednesday^[36], a day of the week^[37]; Four Knights Game^[38], a chess opening^[39]; and FOUR^[40], a building complex^[41], in Germany^[42], founded in 2024^[43].