1155
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 2304
- Proper Divisor Sum (Aliquot Sum)
- 1149
- 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
- 480
- Möbius Function
- 1
- Radical
- 1155
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 31
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n) = 4*n^2 - 1.at n=17A000466
- Number of cells of square lattice of edge 1/n inside quadrant of unit circle centered at 0.at n=38A001182
- 4-dimensional pyramidal numbers: a(n) = (3*n+1)*binomial(n+2, 3)/4. Also Stirling2(n+2, n).at n=9A001296
- a(n) = (4*n+1)*(4*n+3).at n=8A001539
- Coefficients of iterated exponentials.at n=3A001765
- Expansion of (psi(x^2) / psi(-x))^3 in powers of x where psi() is a Ramanujan theta function.at n=9A001937
- Odd squarefree numbers with an even number of prime factors that have no prime factors greater than 31.at n=46A002557
- Numbers that are the sum of 8 positive 5th powers.at n=39A003353
- Numbers that are the sum of 12 positive 7th powers.at n=9A003379
- G.f.: (1 + x^4 + x^7 + 2*x^8 + x^9 + x^12 + x^16)/Product_{i=1..8} (1 - x^i).at n=21A003405
- Discriminants of the known imaginary quadratic fields with 1 class per genus (a finite sequence).at n=54A003644
- Degrees of irreducible representations of alternating group A_11.at n=26A003866
- Degrees of irreducible representations of alternating group A_12.at n=18A003867
- Degrees of irreducible representations of symmetric group S_11.at n=46A003875
- Degrees of irreducible representations of symmetric group S_11.at n=45A003875
- Degrees of irreducible representations of symmetric group S_12.at n=33A003876
- Degrees of irreducible representations of symmetric group S_12.at n=32A003876
- a(n) = n^2 + prime(n).at n=31A004232
- Representation degeneracies for Neveu-Schwarz strings.at n=12A005302
- a(n) = n*(n+2) = (n+1)^2 - 1.at n=33A005563