7617
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10160
- Proper Divisor Sum (Aliquot Sum)
- 2543
- 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
- 5076
- Möbius Function
- 1
- Radical
- 7617
- 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
- 176
- 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
- Hexanacci numbers: a(n+1) = a(n)+...+a(n-5) with a(0)=...=a(4)=0, a(5)=1.at n=19A001592
- Numbers k such that the continued fraction for sqrt(k) has period 86.at n=18A020425
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/2n} satisfy r < s, then r < k/m < (k+4)/m < s for some integer k.at n=28A024848
- 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 58.at n=22A031556
- Denominators of continued fraction convergents to sqrt(438).at n=6A041835
- a(n) = Sum_{k=1..floor((n+1)/2)} T(n,2k-1), array T as in A049777.at n=34A049778
- House numbers: a(n) = (n+1)^3 + Sum_{i=1..n} i^2.at n=17A051662
- Binomial transform of A001371.at n=10A054195
- Engel expansion of -log(log(2)) = 0.36651292... .at n=8A059200
- Row sums of A117683.at n=13A117684
- Triangle read by rows: T(n,k) is the number of deco polyominoes of height n and vertical height (i.e., number of rows) k (1 <= k <= n). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=38A121692
- Number of deco polyominoes of height n and vertical height 3 (i.e., having 3 rows).at n=8A121693
- a(n) = 7*n^2 + 14*n + 1.at n=32A131878
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, -1), (0, 0, 1), (0, 1, 1), (1, -1, 0)}.at n=8A149890
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, -1), (0, 0, 1), (0, 1, 1), (1, -1, 0)}.at n=8A149891
- Recursive triangular symmetrical sequence: A(n,k) := (n - k + 1)A(n - 1, k - 1) + (k)* A(n - 1, k) - (n + 1)*A(n - 2, k - 1).at n=38A153479
- Recursive triangular symmetrical sequence: A(n,k) := (n - k + 1)A(n - 1, k - 1) + (k)* A(n - 1, k) - (n + 1)*A(n - 2, k - 1).at n=42A153479
- If an array is made of columns of -nacci sequences, fibo-, tribo- etc. all starting w. 1,1,2 etc, the NW to SE diagonals can be extended by computation. The above is diagonal 10. See A159741 for details.at n=4A159747
- a(n) = Least i in range [A165583(n),A165583(n+1)] for which abs(A165582(i)) gets the maximum value in that range.at n=30A165584
- a(n) = a(n-2)*2 + floor(sqrt(a(n-1))).at n=24A182559