12957
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 19776
- Proper Divisor Sum (Aliquot Sum)
- 6819
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7392
- Möbius Function
- -1
- Radical
- 12957
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- 125
- Smith Number
- yes
- 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
- Solid partitions of n, distinct along rows.at n=13A002936
- Numbers n such that 109*2^n-1 is prime.at n=8A050580
- Numbers n such that sigma(n - phi(n)) = phi(n + phi(n)).at n=1A074887
- Numbers k such that the k-th prime is of the form 2*j^2 + 1.at n=37A090612
- Symmetrical triangular sequence of Fibonacci numbers (A000045): p(x,n) = Product[1 + Fibonacci[i]*x, {i, 0, n}] + x^n*Product[1 + Fibonacci[i]/x, {i, 0, n}].at n=30A154851
- Symmetrical triangular sequence of Fibonacci numbers (A000045): p(x,n) = Product[1 + Fibonacci[i]*x, {i, 0, n}] + x^n*Product[1 + Fibonacci[i]/x, {i, 0, n}].at n=33A154851
- a(n) = Sum_{k=0..n}((binomial(2*k,k)*Sum_{i=0..n-k}(binomial(k+1,n-k-i)*binomial(k+i,k)))/(k+1)^2)*(n+1).at n=7A270661
- a(n) = 8n^2 - 12n + 1.at n=39A273220
- a(n) = A001567(n) - 2^floor(log_2(A001567(n))).at n=39A295607
- Number of integer partitions of n whose LCM is greater than n.at n=36A327779
- Indices where the cumulative sum of cos(2k+1)^(2k+1) reaches a record low value.at n=39A389560