17261
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17724
- Proper Divisor Sum (Aliquot Sum)
- 463
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16800
- Möbius Function
- 1
- Radical
- 17261
- 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
- 128
- 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
- Centered cube numbers: n^3 + (n+1)^3.at n=20A005898
- Integer nearest a(n-1)/(Pi - 3), where a(0) = 1.at n=5A024587
- "CFK" (necklace, size, unlabeled) transform of 2,1,1,1...at n=31A032140
- a(n) = a(n-1) + a(round(2*(n-1)/3)) + a(round((n-1)/3)) with a(1)=a(2)=1.at n=38A033499
- Numerators of continued fraction convergents to sqrt(181).at n=7A041334
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 7.at n=21A051972
- Numbers n for which there are exactly seven k such that n = k + reverse(k).at n=34A072431
- Odd composite n such that n divides Fibonacci(n) + 1.at n=2A094395
- Odd composites k that divide Fibonacci(k) + 1 but not Fibonacci(k+1).at n=0A094413
- Indices of primes in sequence defined by A(0) = 81, A(n) = 10*A(n-1) + 31 for n > 0.at n=14A101066
- Theorems from propositional calculus, translated into decimal digits.at n=27A101273
- a(n) = (n-2)*a(n-2) + a(n-3), with a(1)=0, a(2)=1, a(3)=1.at n=12A121953
- Composite terms in A128288(n) = A023163(n)/3 for n>1.at n=3A128289
- A084938 * A000012.at n=47A134379
- 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, 0, 0), (0, -1, 1), (1, 0, -1), (1, 1, 1)}.at n=8A149606
- a(n) = 30*n^4 - 120*n^3 + 120*n^2 - 19.at n=6A157411
- a(n) = sum of all divisors of all numbers k such that n^2 <= k < (n+1)^2.at n=16A168012
- Triangle T(n, k, q) = binomial(n, k) - 1 + q^floor(n/2)*binomial(n-2, k-1) with T(n, 0, q) = T(n, n, q) = 1 and q = 3, read by rows.at n=60A173077
- Semiprime centered cube numbers: m^3 + (m+1)^3.at n=8A180082
- Numbers n such that n!10 + 2 is prime.at n=45A204657