12972
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 32256
- Proper Divisor Sum (Aliquot Sum)
- 19284
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4048
- Möbius Function
- 0
- Radical
- 6486
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 50
- 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
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Orders of non-cyclic simple groups (divided by 4).at n=25A008976
- a(n) = floor( n*(n-1)*(n-2)/8 ).at n=48A011890
- 3rd Bernoulli polynomial evaluated at x=n!.at n=4A020545
- Weight distribution of [ 47,24,11 ] binary quadratic-residue code.at n=12A028384
- Weight distribution of [ 47,24,11 ] binary quadratic-residue code.at n=35A028384
- Weight distribution of [ 47,23,12 ] binary quadratic-residue code.at n=3A028385
- a(n) = floor(n^2/4)*(n/2).at n=47A034828
- Cubic star numbers: a(n) = n^3 + 4*Sum_{i=0..n-1} i^2.at n=18A051673
- a(n) is both the sum of n+1 consecutive integers and the sum of the n immediately higher consecutive integers.at n=23A059270
- Minimal m such that n^n-m and n^n+m are both primes, or -1 if there is no such m.at n=29A075468
- Numbers k such that iterating phi(sigma(k)-phi(k)) starting from k leads to the fixed point 8064.at n=25A077096
- a(n) = floor(C(n+6,6)/C(n+2,2)).at n=42A084626
- A transform of the Pell numbers.at n=13A099516
- The (n,r)-th term of the following triangle is T(n)-T(r) for r = 0 to n. The n-th row contains n+1 terms. T(n) = the n-th triangular number = n(n+1)/2. Sequence contains the sum of terms at a 45-degree angle.at n=46A109900
- The indices of cubes (of primes) in the 3-almost primes.at n=11A128302
- E.g.f. satisfies: A(x) = x*(tan(exp(A(x))-1)+1).at n=6A133984
- a(n) = (n-1)!*Sum_{i=1..n-1} (-1)^(i+1)*A027907(n-i+2,i+1)*a(n-i)/(n-i)! for n>0 with a(0)=1, where A027907 is the triangle of trinomial coefficients.at n=5A136168
- Eigentriangle, row sums = A001850, the Delannoy numbers.at n=38A152250
- Smallest k such that p^p -+ k is prime, where p=prime(n).at n=10A157719
- n*A027642(n).at n=46A164869