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“ | Square Party! | ” |
— Sixteen in Various Episodes |
Sixteen, or 16, is a Numberblock made of ten white blocks and six indigo blocks. She is voiced by Beth Chalmers.
Sixteen is a party-loving square who particularly enjoys games.
Appearance[]
Sixteen is made of 10 white blocks with a red border and 6 indigo blocks. Her usual block arrangement is a 4×4 square, with her six indigo blocks shaped like a hat, and the ten block fitting in on top of the six block. She has electric purple square eyes and mouth. Her limbs are dark indigo. She often carries around an air horn, reflecting the colour of her blocks. The horn itself is coloured indigo, while the bottom is red and white.
Sixteen has a team referred to as the "Four Fours", resembling a barbershop quartet. Each Four wears a boater hat with green stripes.
It is known that any Numberblock with 5 factors are not classified as a super rectangle, as Sixteen has 5 factors, but she doesn't have a watch on her left arm.
Personality[]
Sixteen is a very energetic and extroverted square, often partying and playing games with others. She is a natural comedian, often dropping puns and jokes, much to the entertainment (and sometimes exasperation) of her friends. Sixteen is both loud and brash, often using her air horns to celebrate her status as a square. She also provides heavy emphasis on entertaining others, going above and beyond with her party tricks. She often splits into the Four Fours as a result.
Sixteen is also both incredibly friendly and amiable, being quick to entertain her peers and provide accommodations in Square Club. She also tends to resume a leadership position amongst the other squares, usually hosting parties herself while looking out for the interest of the others. She is also, however, shown to be reckless and dives into situations headfirst, and shows little to no fear or anxiety in even unnerving and dangerous situations.
As a square, Sixteen holds great passion for squares, and appears to hold mild disdain for round things.
Episode Appearances[]
- Sixteen (debut)
- Square Club
- Seventeen (doesn’t speak)
- Eighteen
- Loop the Loop
- Nineteen (doesn’t speak)
- Twenty
- Tall Stories
- Flights of Fancy
- I Can Count to Twenty
- Heist
- Sign of the Times
- Divide and Drive
- We're Going on a Square Hunt
- The Big One
- One Hundred (doesn’t speak)
- More To Explore
- The Many Friends Of Twenty
- Twoland
- Two Times Shoe Shop
- Odd Side Story
- Rectangle Racers
- The Team Factor
- Hidden Talents
- Club Picnic
- Figure It Out
- Snow Day Doubles
- Steps Versus Squares
- Puzzle Square
- Four on the Floor
- Square on the Moon
- What If?
- 100 Ways to Leave the Planet
- Double Back
- Making Friends
- Crossover (icon)
- As Tall as the Sun
- The Pattern of Patterns
- Friendly Fours' Beach Day
- We Need Another Hero
- Super Eights Assemble (latest appearance)
Total number of appearances: 40 + 1 (icon)
She appears in 25.95% of all Numberblocks episodes, including the crossover specials.
The Four Fours[]
The Four Fours; they all have the same Barbershop hat with a green ribbon wrapped around it. They appear in six episodes.

Episode Appearances[]
- Sixteen (debut)
- Square Club
- Divide and Drive
- We're Going on a Square Hunt (drawing)
- Four on the Floor
- As Tall as the Sun
- Super Eights Assemble (latest appearance)
- The Octoblock Song (cameo)
Total number of appearances: 6 + 1 (drawing)
Arrangements[]
Square Party! Just like One, Four and Nine, Sixteen can be a square.
2D (62/104,592,937)3D (1) |
Trivia[]
- Sixteen often snorts when she laughs.
- Sixteen is the smallest non-trivial fourth power ().
- Similar to Nine, she is capable of sneezing out her middle block-- in this case, she can sneeze out Four, leaving Twelve.
- She is the third Numberblock to not sing in her debut, the first being Six, and the second being Eight.
- She is the second square to be female, One is the first.
- She is the second square to be a power of two.
- Sometimes, Sixteen's eyes can be asymmetrical.
- The Four Fours are a direct reference to barbershop quartets. Not only are groups typically composed of four members, but the style of barbershop music itself is characterized by four-part harmonies.
- She is the first Numberblock to almost be a super rectangle with 5 factors, the second being Eighty-One (we were unsure whether 5-factors can be super rectangles until 16's debut).
- There is an error in Issue 5 of the 2022 Numberblocks Magazines where on page 9, Sixteen's design heavily resembles Eighteen. Luckily, all other instances of Sixteen in the magazine uses her normal design.
- Sixteen is the second square not to be created in square position, the first is Four. Thirty-Six, Forty-Nine and Sixty-Four followed this pattern if you count their More to Explore drawings. It is unknown if Eighty-One followed this pattern, because he was supposedly figured offscreen.
- Her appearance reveals that when Six attaches to a multiple of ten, her dots disappear.
- Sixteen is the second square that is the opposite gender of their square root, as she is female, while Four is male. The first being Nine. The next three are Thirty-Six, Forty-Nine, and Sixty-Four.
- She sounds similar to Deep Blue from Colourblocks. This is because they share the same voice actor, Beth Chalmers.
- However, despite the voice actor, Deep Blue is a male.
- This is the only time Beth reuses a previous voice.
- She is the fourth Numberblock to be the same gender as both their digits after 10, 11, and 15.
- She is the first square with permanent square-eyes to not have eyebrows.
- She is the second female Numberblock to be in the 4 times tables.
- Sixteen is the first even square Numberblock to sneeze.
- She is the last square number to get a musical number.

Screenshot of the mistake by Numberblock63Official.
- Her gender was mistaken in a YouTube description once.
- She, Eight, and Four are the only Friendly Fours that are not super rectangles.
- This is because Four does not have enough prime factors while Eight and Sixteen repeat prime factors (which causes you to make less factors).
Number[]
- 16's numeral means:
- 18 in Duodecimal.
- 22 in Hexadecimal.
- 24 in Octodecimal
- 26 in Vigesimal.
- 14 in Octal
- 16's value means:
- 0001 0000 in Binary
- 14 in Duodecimal
- 10 in Hexadecimal
- G in Octodecimal/Vigesimal.
- 20 in Octal
Errors[]
- In a magazine, Sixteen has an array display and rectangular eyes (Eighteens eyes), despite her not being a super rectangle (she onli has 5 factors), and her being square.