17693
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 19068
- Proper Divisor Sum (Aliquot Sum)
- 1375
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16320
- Möbius Function
- 1
- Radical
- 17693
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 79
- 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() = 1,3,... [ A037257 ], differences = 2,... [ A037258 ] and 2nd differences [ A037259 ] are disjoint and monotonic; adjoin next free number to 2nd differences unless it would produce a duplicate in which case ignore.at n=41A037257
- Same rule as Aitken triangle (A011971) except a(0,0)=1, a(1,0)=0.at n=49A046934
- Sequence formed from rows of triangle A046934.at n=39A046935
- Revert transform of 2*x*(1 - x - x^3 + x^4 - x^5)-x/(1+x).at n=8A049180
- Self-convolution of A073711.at n=36A073712
- Positions of records in A034694.at n=46A120857
- G.f.s of the z^p coefficients of the polynomials in the GF4 denominators of A156933.at n=13A157705
- Positive numbers y such that y^2 is of the form x^2+(x+857)^2 with integer x.at n=6A160206
- Beach-Williams Pell numbers of type k^2 + 4.at n=3A212083
- Numbers n where tau(n) and n-tau(n) are perfect squares, with tau(n) the number of divisors of n (A000005).at n=35A245197
- a(n) = number of steps to reach 0 when starting from k = (n^3)-1 and repeatedly applying the map that replaces k with k - A055401(k), where A055401(k) = the number of positive cubes needed to sum to k using the greedy algorithm.at n=52A261228
- Semiprimes of the form k^2 + 4.at n=29A360741
- T(n,k) is the number of permutations of [n] having exactly k pairs of integers i<j in [n] such that their cycle minima have opposite sorting order; triangle T(n,k), n>=0, 0<=k<=A125811(n)-1, read by rows.at n=49A381529