17919
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 28392
- Proper Divisor Sum (Aliquot Sum)
- 10473
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10800
- Möbius Function
- 0
- Radical
- 5973
- Omega Function (Ω)
- 4
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 247
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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 k*(k+1)/2 + 1 is a square.at n=11A006451
- Number of partitions of n that do not contain 9 as a part.at n=37A027343
- Numbers k such that both k and k+1 are sums of two positive cubes.at n=4A085323
- a(n) = 2*a(n-1) + a(n-2) + 1, a(0) = 1, a(1) = 2.at n=11A098790
- Numbers which are the sum of two positive cubes and divisible by 11.at n=25A101852
- a(n) = 4*n^3 - 6*n^2 + 1.at n=17A141530
- A sequence of asymptotic density zeta(10) - 1, where zeta is the Riemann zeta function.at n=17A143036
- a(n) = (n+3)^2*n/2 + 1.at n=31A154560
- a(n) = 512n - 1.at n=34A158011
- a(n) = 62*n^2 + 1.at n=17A158676
- a(n) = 70*n^2 - 1.at n=15A158736
- Ascending sequence of numbers such that the sum of any two distinct elements (even + odd) is a prime number.at n=36A180743
- Numbers k such that triangular(k)+1 is a prime power (A025475).at n=7A226103
- Numbers k such that the distance between the k-th triangular number and the nearest square is at most 1.at n=21A229083
- Numbers k such that the distance between the k-th triangular number and the nearest square is exactly 1.at n=16A229131
- a(n) = Sum_{i=0..n} digsum_5(i)^4, where digsum_5(i) = A053824(i).at n=29A231671
- Numbers n such that n^10+10 is prime.at n=27A239347
- Number of partitions p of n such that (maximal multiplicity over the parts of p) = (number of numbers in p having multiplicity > 1).at n=49A241132
- Number of length n+3 0..n arrays with no four elements in a row with pattern abab (with a!=b) and new values 0..n introduced in 0..n order.at n=5A243037
- Number of length n+3 0..6 arrays with no four elements in a row with pattern abab (with a!=b) and new values 0..6 introduced in 0..6 order.at n=5A243042