On the seven-segment displays of pocket calculators and digital watches, 7 is the number with the most common glyph variation (0, 6 and 9 also have variant glyphs). Most calculators use three line segments, but in some brands of calculators, 7 is written with four line segments., The fact is that, historically, the number 7 has played a significant role in society, culture, religion, and even psychology. Here are 7 reasons we are so drawn to the number: 1. It has been, See the number seven on a number line, temore. Jack Hartmann's I Can Show the Number 7 in Many Ways teaches us about the number 7. Learn the different ways number 7 can be represented. See, The number 7 is often considered lucky, and it has a definite mystique, perhaps because it is a prime number—that is, it cannot be obtained by multiplying two smaller numbers together., Your guide to the number 7, an odd number which is prime. Mathematical info, prime factorization, fun facts and numerical data for STEM, education and fun., .