Tommy Robinson: Where's the Money Gone? Hear from survivors of toxic relationships. Some big names here but fame can't help them now. A 17-year-old boy is found with catastrophic head injuries. In mathematics, the number four is an even number and the smallest composite number. Four is also the second square number after one. A small minority of people have four fingers on each hand and four toes on each foot. [source?] Four squared is 16, and four doubled is 8. Four is the second square number (a square number is an integer that can be written as the square of some other integer) and the second centered triangular number. A West Arabic numeral, ultimately from Indic numerals (compare Devanagari ४ (4)), a cursive form of four lines (to represent the number four) arranged in the shape of a cross (resembling +). In internet slang, 4 can replace the word for (as four and for are pronounced similarly). For example, messaging 4 u instead of for you when talking to someone. Noun 1. 4 - the cardinal number that is the sum of three and one IV, Little Joe, quadruplet, quartet, quatern, four, quaternion, quaternity, tetrad. Created by teachers, learn how to show 4 in a ten frame. Learn to draw 4 tally marks. See the number 4 with objects that sometimes come to life for a fun surprise! Explore fascinating facts about the number 4. Discover its significance in various cultures, including its symbolism and representations in numerology, astrology, and mythology. Discover the fascinating world of the number 4! Explore its meanings, facts, religious significance, angel number interpretations, and its role in arts and literature. Four is the largest number within the subitizing range and one of two numbers that is both a square and a highly composite number (the other being thirty-six), making quaternary a convenient choice for a base at this scale. Despite being twice as large, its radix economy is equal to that of binary.