12738
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
- 4
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 27936
- Proper Divisor Sum (Aliquot Sum)
- 15198
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3840
- Möbius Function
- 1
- Radical
- 12738
- 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
- 107
- 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
- yes
- Odd
- no
Appears in sequences
- "AFK" (ordered, size, unlabeled) transform of 2,2,2,2,...at n=17A032005
- Trajectory of 1 under map n->25n+1 if n odd, n->n/2 if n even.at n=9A033969
- Numbers k such that 2^k + 15 is prime.at n=44A057197
- Leading diagonal of A083173.at n=43A083174
- Triangle read by rows: T(n,k) is the number of 0-1-2 trees (i.e., ordered trees with all vertices of outdegree at most two) with n edges and k pairs of adjacent vertices of outdegree 2.at n=40A126218
- Number of binary strings of length n with equal numbers of 0000 and 1111 substrings.at n=15A164154
- Number of permutations of 2 copies of 1..n with all adjacent differences <= 1 in absolute value.at n=16A177282
- Shiraishi numbers: a parametrized family of solutions c to the Diophantine equation a^3 + b^3 + c^3 = d^3 with d = c+1.at n=21A226903
- Least number k >= 0 such that (n!+k)/n is prime.at n=65A245695
- Numbers k with the property that p = k^2 - 13 and q = k^2 + 13 are consecutive primes.at n=28A248785
- Number of (n+2) X (4+2) 0..3 arrays with every 3 X 3 subblock row and column sum not equal to 0 3 5 6 or 7 and every 3 X 3 diagonal and antidiagonal sum equal to 0 3 5 6 or 7.at n=19A252250
- Least k such that prime(n) is the smallest prime p for which k^2 + p^2 is also prime, or 0 if none.at n=50A263466
- a(n) = 3*(n+1)*(9*n+4).at n=21A304503
- Expansion of (-1 + Product_{k>=1} 1 / (1 + (-x)^k))^6.at n=17A341245