6
domain: N
Properties
Digital Properties
- Digit Count
- 1
- Digit Sum
- 6
- Digital Root
- 6
- Palindromic Number
- yes
- Repdigit
- yes
- Automorphic
- yes
- Kaprekar Number
- no
- Multiplicative Persistence
- 0
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 12
- Proper Divisor Sum (Aliquot Sum)
- 6
- Abundant Number
- no
- Perfect Number
- yes
- Deficient Number
- no
- Highly Composite
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2
- Möbius Function
- 1
- Radical
- 6
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- yes
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- yes
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- yes
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- yes
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- yes
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- yes
- Collatz Steps
- 8
- Smith Number
- no
Classification
- Natural
- yes
- Even
- yes
- Odd
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- yes
- Carmichael Number
- no
Names
- German
- sechs· ordinal: sechste
- English
- six· ordinal: sixth
- Spanish
- seis· ordinal: sexto
- French
- six· ordinal: sixième
- Italian
- sei· ordinal: sesto
- Latin
- sex· ordinal: sextus
- Portuguese
- seis· ordinal: sexto
Appears in sequences
- Number of groups of order n.at n=42A000001
- Number of groups of order n.at n=78A000001
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=25A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=28A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=34A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=37A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=43A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=49A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=50A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=52A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=53A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=60A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=74A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=75A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=80A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=86A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=90A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=91A000003
- Number of classes of primitive positive definite binary quadratic forms of discriminant D = -4n; or equivalently the class number of the quadratic order of discriminant D = -4n.at n=98A000003
- d(n) (also called tau(n) or sigma_0(n)), the number of divisors of n.at n=11A000005