1227
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
- 4
- Divisor Sum
- 1640
- Proper Divisor Sum (Aliquot Sum)
- 413
- 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
- 816
- Möbius Function
- 1
- Radical
- 1227
- Omega Function (Ω)
- 2
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 132
- Smith Number
- no
- Vampire Number
- 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
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers that are not the sum of 4 tetrahedral numbers.at n=50A000797
- a(n) = 5*a(n-2) - 2*a(n-4), with initial terms 0,1,1,3.at n=11A005824
- Coordination sequence T1 for Zeolite Code AST.at n=26A008036
- Coordination sequence T6 for Zeolite Code BOG.at n=25A008054
- Coordination sequence T3 for Zeolite Code GOO.at n=24A008113
- Molien series for 4-dimensional complex reflection group of order 7680 (in powers of x^4).at n=55A008669
- Expansion of (1+x^10)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=44A008771
- a(0) = 1, a(n) = n^2 + 2 for n > 0.at n=35A010000
- a(0) = 1, a(n) = 25*n^2 + 2 for n > 0.at n=7A010015
- Pisot sequence E(4,27): a(n) = floor(a(n-1)^2/a(n-2)+1/2) for n>1, a(0)=4, a(1)=27.at n=3A010910
- a(n) = floor(n*(n - 1)*(n - 2)/32).at n=35A011914
- Discriminants of imaginary quadratic fields with class number 4 (negated).at n=47A013658
- Least d such that period of continued fraction for sqrt(d) contains n (n^2+2 if n odd, (n/2)^2+1 if n even).at n=34A013945
- a(n) = n-2 + Sum_{i = 1..n-2} (a(i+1) mod a(i)) for n >= 3 with a(1) = a(2) = 1.at n=52A022856
- Numbers k such that Fibonacci(k) == 2 (mod k).at n=22A023174
- a(n) = s(1)*s(n) + s(2)*s(n-1) + ... + s(k)*s(n+1-k), where k = floor((n+1)/2), s = (Fibonacci numbers).at n=12A024458
- a(n) = least m such that if r and s in {h/(1 + h^2): h = 1,2,...,n} satisfy r < s, then r < k/m < s for some integer k.at n=39A024828
- Position of n^3 + 9 in A024975.at n=21A024979
- a(n) = Sum_{j=0..n} Sum_{i=0..n} T(j,i), T given by A026736.at n=9A026745
- a(n) = Sum{T(n,k)*T(n,2n-k)}, 0<=k<=n-1, T given by A027926.at n=6A027991