17409
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 26560
- Proper Divisor Sum (Aliquot Sum)
- 9151
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9936
- Möbius Function
- -1
- Radical
- 17409
- 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
- 172
- 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
- a(n) = Fibonacci(n)*2^n + 1.at n=9A006483
- E.g.f.: exp(sin(x)-log(x+1)).at n=8A013341
- Numbers k > 1 such that, in base 8, k and k^2 contain the same digits in the same proportion.at n=20A061662
- Odd numbers k such that the number of 1's in binary representation of k equals omega(k), the number of distinct primes in the factorization of k.at n=25A071595
- Interprimes (A024675) which are of the form s*prime, s=21.at n=34A075296
- a(n) = 512*n + 1.at n=34A076338
- 1 + (n+6)*2^(n-1).at n=11A115618
- E.g.f. satisfies: A(x) = x*(sec(exp(A(x))-1)).at n=7A133553
- a(n) = A145818(2n-1).at n=40A145850
- a(n) = 68*n^2 + 1.at n=16A158732
- a(0)=0; thereafter a(n) = (3*n+1)*2^(n-2)+1.at n=12A170881
- Number of disconnected 4-regular simple graphs on n vertices with girth exactly 4.at n=24A185044
- Triangular array D(n,k) counting disconnected k-regular simple graphs on n vertices with girth at least 4.at n=87A185204
- Number of disconnected 4-regular simple graphs on n vertices with girth at least 4.at n=24A185244
- Numbers n such that the decimal number concat(7,n) is a square.at n=27A273362
- Numbers with exactly 3 ones in both binary and ternary representations.at n=42A281004
- Row sums of triangle A297495.at n=11A297186