3842
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 6156
- Proper Divisor Sum (Aliquot Sum)
- 2314
- 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
- 1792
- Möbius Function
- -1
- Radical
- 3842
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 144
- 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
- a(n) = a(n-1) + 3*a(n-2).at n=10A006138
- Coordination sequence T4 for Zeolite Code LTN.at n=43A008143
- a(0) = 1, a(n) = 15*n^2 + 2 for n>0.at n=16A010005
- Prefix (or Levenshtein) codes for natural numbers.at n=18A010097
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 60.at n=20A031558
- Concatenation of n and n + 4 or {n,n+4}.at n=37A032609
- Numbers whose set of base-15 digits is {1,2}.at n=19A032935
- Composite numbers whose 3 prime factors are distinct in length.at n=34A046443
- a(n) = Sum_{m=1..n, k=1..m} T(m,k), array T as in A049834.at n=29A049836
- Convolution triangle of A000129(n) (Pell numbers).at n=38A054456
- Pell numbers A000129(n+1) (without P(0)) convoluted twice with itself.at n=6A054457
- Number of right triangles of a given area required to form successively larger squares.at n=30A060626
- Numbers k such that k*2^m+1 is prime for exactly one exponent m in the range 0<=m<=k.at n=33A061155
- Trajectory of 3 under map n->7n-1 if n odd, n->n/2 if n even.at n=20A063871
- Values of k for which A065358(k) is 0.at n=39A064940
- Even numbers k such that k/2 is nonprime and sigma(k+1) > sigma(k).at n=38A067827
- Numbers n such that Rd(n) + Ld(n) +/-1 is prime, where Rd and Ld are the right- and left-digital factorial functions.at n=42A071714
- a(n) = n-th multiple of n with digit sum n.at n=16A082260
- a(n) = 8*a(n-1) - a(n-2), starting with a(0) = 2 and a(1) = 8.at n=4A086903
- A number triangle associated with the Chebyshev polynomials of the first kind.at n=61A101161