12538
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18810
- Proper Divisor Sum (Aliquot Sum)
- 6272
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6268
- Möbius Function
- 1
- Radical
- 12538
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 63
- 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
- yes
- Odd
- no
Appears in sequences
- 4th powers written backwards.at n=16A002108
- Numbers k such that the continued fraction for sqrt(k) has period 79.at n=9A020418
- Expansion of (1-x)/(1+2*x-x^2+x^3).at n=10A078058
- a(1)= 10000, a(2)= 10000; for n>2, a(n)= ( a(n-2) + a(n-1) ) (mod 20000).at n=32A096973
- Numbers n such that 9*10^n + 7*R_n - 6 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=11A103105
- Semiprimes whose digit reversal is a nontrivial power.at n=30A108849
- Semiprimes (A001358) whose digit reversal is a powerful(1) number (A001694).at n=36A115688
- Semiprimes (A001358) whose digit reversal is a square.at n=25A115710
- Expansion of (1+x)/(1-2x-x^2-x^3).at n=10A116413
- Triangle read by rows : T(n,0) = n+1, T(n,k)=0 if k<0 or if k>n, T(n,k) = k*T(n-1,k) - T(n-1,k-1).at n=49A159881
- Values of x in A216363.at n=18A216382
- Least positive integer k such that prime(prime(prime(k)))+ prime(prime(prime(k*n))) = 2*prime(prime(p)) for some prime p.at n=57A261583
- Maximal term of TRIP-Stern sequence of level n corresponding to permutation triple (e,132,e).at n=29A271489
- G.f.: 1/(1-x)^4 * Product_{k>=1} (1 + x^k).at n=16A325952
- Number of integer partitions of n such that (length) * (maximum) >= 2*n.at n=34A361906
- Number of integer partitions of n with origin-to-boundary graph-distance equal to 4.at n=54A384562