4861
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4862
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 4860
- Möbius Function
- -1
- Radical
- 4861
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 165
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 651
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/5.at n=13A001135
- Catalan numbers - 1.at n=7A001453
- From a Goldbach conjecture: records in A185091.at n=32A002092
- Primes of the form 2^q*3^r*5^s + 1.at n=51A002200
- Coordination sequence T1 for Zeolite Code NON.at n=42A008212
- Coordination sequence for Paracelsian.at n=47A008260
- Coordination sequence T5 for Zeolite Code VNI.at n=43A009911
- Primes that remain prime through 2 iterations of function f(x) = 3x + 8.at n=45A023248
- Primes that remain prime through 2 iterations of function f(x) = 6x + 1.at n=40A023256
- a(n) = T(n,[ n/2 ]), where T is the array defined in A026082.at n=13A026094
- Triangle read by rows: square of the lower triangular mean matrix.at n=46A027446
- a(n) = (H(n) - 1)*lcm{1,...,n}, where H(n) is the n-th harmonic number.at n=9A027457
- Numerator of 1/n + 2/(n-1) + 3/(n-2) + ... + (n-1)/2 + n.at n=8A027612
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 58 ones.at n=0A031826
- Lower prime of a difference of 10 between consecutive primes.at n=63A031928
- Binomial transform of [ 1, 0, 1, 1, 3, 6, 15, 36, 91, 231, 595, ... ], which is essentially binomial(Fibonacci(k) + 1, 2).at n=9A033191
- Expansion of sum ( q^n / product( 1-q^k, k=1..6*n), n=0..inf ).at n=24A035298
- a(n) = A036800(n)/2.at n=7A036826
- All differences C(j)-C(i), j>i, of Catalan numbers A000108.at n=36A047075
- Triangle of numbers T(n,k) = number of permutations of (1,2,...,n) with longest increasing subsequence of length k (1<=k<=n).at n=37A047874