17641
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
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 20160
- Proper Divisor Sum (Aliquot Sum)
- 2519
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15312
- Möbius Function
- -1
- Radical
- 17641
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 141
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 70 ones.at n=36A031838
- Schoenheim bound L_1(n,n-4,n-5).at n=33A036830
- Number of partitions of 5n such that cn(1,5) = cn(4,5) < cn(2,5) = cn(3,5) <= cn(0,5).at n=13A036891
- Base-5 digits are, in order, the first n terms of the periodic sequence with initial period 1,0,3.at n=6A037591
- Number of 4-level labeled linear rooted trees with n leaves.at n=5A050352
- Expansion of 1/(1 - 5*x - 4*x^3).at n=6A060928
- a(n) = floor(n*n!/2 + 1).at n=6A082426
- Sieve performed by successive iterations of steps where step m is: keep m terms, remove the next 3 and repeat; as m = 1,2,3,.. the remaining terms form this sequence.at n=18A112561
- Number of degeneracies on the sets of n ordinary trees with n vertices. These are the values of the Randic index, 'chi', in Table 15 of the paper by Elena V. Konstantinova and Maxim V. Vidyuk.at n=8A125068
- a(n) = (n-1)*(n+2)*(2*n+11)/2.at n=23A130862
- a(n) = 2*a(n-1) - a(n-2) - a(n-4).at n=26A131041
- Numbers k such that (k-1)^(k+1) - k^k is prime.at n=8A134985
- Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 1), (1, 0)}.at n=13A151255
- Number of ways to place zero or more nonadjacent 1,1 2,1 3,0 3,1 3,2 4,1 5,1 polyhexes in any orientation on a planar n X n X n triangular grid.at n=7A155325
- Numerator of Euler(n, 9/31).at n=3A157690
- a(n) = 10*n^2 + 1.at n=42A158187
- a(n) = 40*n^2 + 1.at n=21A158602
- Number of ways to write n as the root-mean-square (RMS) of a set of distinct positive integers.at n=12A164283
- Number of partitions of n with no part equal to 1 or 3.at n=53A181531
- Centered 28-gonal numbers.at n=35A195314