4145
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 4980
- Proper Divisor Sum (Aliquot Sum)
- 835
- 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
- 3312
- Möbius Function
- 1
- Radical
- 4145
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 38
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = n^3 + 3*n + 1.at n=16A005491
- Coordination sequence T2 for Zeolite Code SGT.at n=40A008230
- Expansion of 1/((1-2x)(1-8x)(1-11x)).at n=3A016318
- a(n) = least m such that if r and s in {1/1, 1/4, 1/7,..., 1/(3n-2)} satisfy r < s, then r < k/m < s for some integer k.at n=42A024822
- (d(n)-r(n))/5, where d = A008778 and r is the periodic sequence with fundamental period (0,3,1,0,1).at n=46A026053
- Concatenation of n and n + 4 or {n,n+4}.at n=40A032609
- a(n)=A033002(n)/5.at n=46A043308
- Numbers whose base-16 representation has exactly 4 runs.at n=31A043677
- Numbers whose base-4 representation contains exactly four 0's and two 1's.at n=15A045035
- Numbers whose base-4 representation contains exactly four 0's and no 2's.at n=30A045057
- Numbers whose base-4 representation contains exactly four 0's and one 3.at n=29A045082
- a(n) = Sum_{i=0..2n} (-1)^i * T(i,2n-i), array T as in A048149.at n=36A049713
- Sum of numbers in range 10*n to 10*n+9.at n=41A053743
- Fourth spoke of a hexagonal spiral.at n=37A056108
- A Collatz-Fibonacci mixture: a(1) = 1, a(2) = 2, a(n+2) = a(n+1)/2+a(n)/2 if a(n+1) and a(n) have the same parity, a(n+2) = a(n+1)+a(n) otherwise.at n=34A069202
- Number of different two-dimensional burst patterns in the hexagonal graph.at n=5A093426
- a(n) is the least number of prime factors in any non-deficient number that has the n-th prime as its least prime factor.at n=42A107705
- a(n) is the least number of prime factors for any abundant number with p_n (the n-th prime) as its least factor.at n=42A108227
- Numbers j such that (3^j)*(47#) -1 is prime.at n=30A110116
- Semiprimes in A056108.at n=11A113527