Number 17 in Math.   Number 17        (More Math. pages)

[Trivia]  Modernly, the 17^th wedding anniversary is named furniture (or watch) anniversary.

 

[Biology]  The number of bones in a human spinal column: 12 thoracic vertebrae (upper back) and 5 lumbar vertebrae (lower back).

 

[Calendar]  The St. Patrick’s Day is on 17 March.

 

[Calendar]  The U.S. Citizenship Day is on 17 September.

 

[Chemistry]  The atomic number of Chlorine (Cl).

 

[Flag]  The number of white stars surround the letter “O” in white and red in the blue triangle on the Ohio state flag, representing the 17^th state of the Union. They are separated into 2 groups of 13 stars (for the 13 original states of the Union) and 4 stars at the peak of the triangle.

 

[History]  The North 17^th parallel (17^o latitude line) divided North Vietnam and South Vietnam before 1975.

 

[History]  Ohio became the 17^th state of the U.S. on 1 March 1803. (But the Congress did not voted on its resolution until 7 August 1953).

 

[History]  The 17^th U.S. President: Andrew Johnson (Republican, North Carolina, 1865-1869). There was no Vice President.

 

[Language]  Prefixes: Septende-, Septendec-, Heptadeca-…

 

[Literature]  The number of syllables in “Haiku”, an ancient form of Japanese poetry is composed of three lines, with five syllables in the first, seven syllables in the second and five syllables in the third.

 

[Math.]  An absolute prime number (or permutable prime number): both numbers 17 and 71 are prime or in fact, absolute prime.

 

[Math.]  The only prime number that is the sum of 4 consecutive prime numbers: 17 = 2+3+5+7. (All prime numbers less than 10). The 7^th prime number.

 

[Math.]  A Mersenne exponent: 2¹⁷–1 = 131071 is the 6^th Mersenne prime number.

 

[Math.]  40,578,660 = 2×2×3×3×5×17×89×149, where each digit 1-9 appears exactly twice.

 

[Math.]  510,510 is the product of first 7 prime numbers, of 2 consecutive numbers and of 4 consecutive Fibonacci numbers: 510,510 = 2×3×5×7×11×13×17 = 714×715 = 13×21×34×55.

 

[Math.]  17³ = 4913 = (4+9+1+3)³.

17⁴ = 83,521 = (8+3+5+2–1)⁴.

17⁶ = 24,137,569 = (24–13+75–69)⁶.

 

[Math.]  The 3^rd Fermat number is a prime number.

 

[Math.]  The 17-sided regular polygon (heptadecagon) is constructible by using only straightedge and compass. The great German mathematician Carl Friedrich Gauss discovered the construction in March 1796.

 

[Math.]  The number of vertices/points of the star that was the shape of the base for the statue of the great German mathematician Carl Friedrich Gauss, placed at Brunswick, his birthplace. In March 1796, he discovered how to divide a circle into 17 equal arcs, by using only straightedge and compass.

 

[Math.]  One of only 2 prime numbers of the form n^(nⁿ)+1: 2 = 1^(1¹)+1 and 17 = 2^(2²)+1.

 

[Math.]  One of only a few prime numbers of the form (x^y+y^x): 17 = 2³+3².

 

[Math.]  The number of non-abelian groups of order less thanor equal 17.

 

[Math.]  14,368,485 = 3×5×17×29×29×67, using each of 9 digits 1-9 twice.

 

[Math.]  A pair of prime numbers (p = 17, q = 3313) found by Stephens (1971), that 2 numbers of the form (p^q–1)/(p–1) and (q^p–1)/(q–1) have a common prime factor 112643, as a counter-example to the Feit-Thompson conjecture that no such pair of prime numbers could exist.

 

[Math.]  The product of the first 8 consecutive prime numbers, divided by 10:  2×3×5×7×11×13×17×19/10 = 969,969 is a palindromic number.

 

[Math.]  A supersingular prime numbers factors of the order of the Monster group M:

2⁴⁶×3²⁰×5⁹×7⁶×11²×13³×17×19×23×29×31×41×47×59×71 =

= 808017424794512875886459904961710757005754368000000000.

 

[Math.]  No odd Fibonacci number is divisible by number 17.

 

[Money]  The number of stars circling around the flying eagle on the U.S. one dollar coin (golden coin).

 

[Movie]  NC-17, one of 5 basic movie ratings: G (General Audiences), PG (Parental Guidance Suggested), PG-13 (Parents Strongly Cautioned, for children under 13), R (Restricted, for children under 17) and NC-17 (No one 17 and Under Admitted).

 

[Movie]  Names of TV shows/series or movies: “Stalag 17” and “17 Again”.

 

[Phone]  The emergency telephone numbers dialing within Guadeloupe are 17 and 18.

 

[Sport]  The isosceles triangle of sides 12-12-17 (inches) at the top of the home plate (whose shape is a non-regular pentagon) in baseball is not quite a right triangle as specified, since 12²+12² = 288 < 17² = 289. Its largest angle is an obtuse angle of 90.2^o.

 

[Sport]  The 1972 Miami Dolphins is still the only NFL team with a single perfect season at win/lose record 17-0.

 

[Sport]  The NFL (National Football League) season lasts 17 weeks (before playoffs and Super Bowl). Each team is scheduled to play 16 games, with one bye week for each team, which is scheduled in the first half of the season. That is the last possible bye week is week 9.

 

[Tech.]  Apollo 17 is the last Apollo spaceship of Moon landing to carry out geological studies and brought rock and soil back to the Earth, on 7-14 December 1972. Its commander, Eugene Cernan, is the last man to leave the moon.

 

[Tech.]  The number of digits in a complete barcode or UPC (Universal Product Code for North America) used for mass-marketed books: a 12-digit UPC (6-digit manufacturing code, 5-digit product code and 1 check digit) and a 5-digit bi-pad.

 

[Tech.]  The VIN (Vehicle Identification Number) of an autompobile has 17 digits to encode information on: manufacturer, plant location, engine style, body style, model year and restraint system, where the middle (9^th) digit of the number a₁…a₉…a₁₇ is for the check digit:

a₉ = 8a₁+7a₂+6a₃+5a₄+4a₅+3a₆+2a₇+10a₈+9a₁₀+8a₁₁+7a₁₂+6a₁₃+5a₁₄+4a₁₅+3a₁₆+2a₁₇, modulo 11.