1215
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 2184
- Proper Divisor Sum (Aliquot Sum)
- 969
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 648
- Möbius Function
- 0
- Radical
- 15
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 163
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Largest order of automorphism group of a tournament with n nodes.at n=14A000198
- EULER transform of 3, 2, 2, 2, 2, 2, 2, 2, ...at n=10A000713
- Number of partitions of n into at most 4 parts.at n=51A001400
- Numbers that are the sum of 5 positive 5th powers.at n=25A003350
- Numbers of the form 3^i*5^j with i, j >= 0.at n=20A003593
- Degrees of irreducible representations of Janko group J3.at n=11A003906
- Degrees of irreducible representations of Janko group J3.at n=10A003906
- a(n) = 5*3^n.at n=5A005030
- Number of walks on square lattice.at n=5A005565
- Number of entries in first n rows of Pascal's triangle not divisible by 3.at n=79A006048
- Related to representations as sums of Fibonacci numbers.at n=28A006133
- Percolation series for directed square lattice.at n=18A006462
- Number of triangles with integer sides and area = n times perimeter.at n=44A007237
- Coordination sequence T1 for Zeolite Code BIK.at n=21A008047
- Coordination sequence T11 for Zeolite Code MFI.at n=22A008163
- Degrees of irreducible representations of group U5(2).at n=46A008947
- Degrees of irreducible representations of group U5(2).at n=45A008947
- Coordination sequence T2 for Zeolite Code -ROG.at n=26A009860
- Coordination sequence T3 for Zeolite Code -WEN.at n=25A009864
- Triangle of coefficients in expansion of (1+3*x)^n.at n=25A013610