Multiplicative Identity

Even Prime

Number of Spatial Dimensions We Live In

Number of Colors Sufficient to Color All Planar Maps

Number Of Platonic Solids

Smallest Perfect Number

Smallest Number of Sides of a Polygon that Cannot be Constructed with Straightedge and Compass

Largest Cube in Fibonacci Sequence

Maximum Number of Cubes Needed to Sum Any Integer

Base of Our Number System

Smallest Two-Digit Palindrome

Smallest Abundant Number

Number of Archimedian Solids

Smallest Even that Has No Solution to the Totient Function

Smallest Composite Number n that There is One Group of Order n

Only Number that Has x^y=y^x for x≠y

Number of Wallpaper Groups

Only Positive Number that is Twice the Sum of its Digits

Maximum Number of Fourth Powers to Sum Any Number

Number of Rooted Trees with Six Vertices

Smallest Number of Distinct Squares Needed to Tile a Square

Number of Partitions of 8

Smallest Number of Integer-Side Boxes that Tile a Box So that No Two Boxes Share a Common Length

Largest Number Divisible by All Numbers Less Than its Square Root

Smallest Square that is the Sum of Two Squares

Directly Between a Square and a Cube

Largest Number that is the Sum of the Digits of its Cube

Only Perfect Number with Two Digits

Seventh Lucas Number

Largest Number that All Numbers Relatively Prime to it are Prime

Mersenne Prime of 2^5

Smallest Non-Trivial Fifth Power

Largest Number that is not a Sum of Distinct Triangular Numbers

Smallest Number With Property that it and Its Neighbors Have an Equal Amount of Divisors

Number of Hexominoes

Smallest Non-Trivial Number that is a Triangular Square

Maximum Number of Fifth Powers Needed to Sum any Number

Last Roman Numeral Written Lexicographically

Smallest Number that has Three Partitions into Three Parts that have the Same Product

Only Number Whose Letters are in Alphabetical Order

Sum of First Six Primes

The Answer to the Ultimate Question of Life, the Universe, and Everything

Number of One-Sided 7-iamonds

Number of Derangements of Five Items

Third Kaprekar Number

Number of Distinct Arrangements of Non-Attacking Queens on a 9x9 Chessboard

Largest Number of Cubes that Cannot Tile a Cube

Smallest Number with Ten Divisors

Smallest Number that it and its Neighbors are Squareful

Smallest Number that can be Written as the Sum of Squares in Two Ways

Sixth Motzkin Number

Fifth Bell Number

Only Two-Digit Number that is Reversed in Hexadecimal

Smallest Number that can be Written as the Sum of Three Squares in Three Ways

Largest Triangular Number in Fibonacci Sequence

Number of Reduced 5x5 Latin Squares

111 in Base 7

Number of Communative Semigroups of Order 4

Number of Stellations of an Icosahedron

Smallest Number Divisible by 1-6

Third Secant Number

Smallest Number that can be Written as the Sum of Three Distinct Squares in Two Ways

Number of Partially Ordered Sets of Five Elements

Smallest Number with Seven Divisors

Smallest Number that Becomes a Square if its Reverse is Added or Subtracted from It

Number of 8-iamonds

Smallest Number that is Palindromic in Bases 5 and 6

Last Two-Digit String that Appears in Pi

Smallest Number Written with Distinct, Congruent Digits

Smallest Weird Number

Smallest Number > 60 that Divides into the Sum of the Primes Less Than It

Smallest Non-Square Number Whose Square Root Has a Six Outside the Radical

Smallest Multi-Digit Number that is One Less than Twice its Reverse

Number of non-Hamiltonian Polyhedra with a Minimum Number of Vertices

Number of Orderings of 4 Objects with Ties Allowed

Fifth 1-Automorphic Number

Largest Number that Cannot be Written as Sum of Numbers Whose Reciprocals Sum to One

Smallest Number that can be Written as Sum of Four Distinct Squares in Three Ways

Largest Number < 80 Whose Digits Form an Arithmetic Sequence

Smallest Number n Where n and n+1 are Both Products of Four or More Primes

Smallest Non-Trivial Number that is the Square of the Sum of Its Digits

Number of 6-Hexes

Number of Strongly Connected Digraphs with Four Vertices

Largest Order of a Permutation with Fourteen Elements

Largest n for Which 1^2+2^2+3^2...+n^2=1+2+3...+m Has a Solution

222 in Base 6

Sum of Squares of First Four Primes

Smallest Number Whose Square has no Isolated Digits

8^1+9^2

Number of Degrees in a Right Angle

Smallest Pseudoprime in Base 3

Number of Different Arrangements of Eight Non-Attacking Queens on an 8x8 Chessboards

333 in Base 5

Sixth Smith Number

Number of Planar Partitions of 10

Smallest Number that can be Written as Difference of Two Squares in Four Ways

Smallest Number Such that its First Three Multiples Contain the Digit Nine

Smallest Number Such that its First Five Multiples Contain the Digit Nine

Largest Two-Digit Number

Smallest Square that is the Sum of Four Consecutive Cubes

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