17534
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 28728
- Proper Divisor Sum (Aliquot Sum)
- 11194
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7960
- Möbius Function
- -1
- Radical
- 17534
- 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
- 79
- 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
- yes
- Odd
- no
Appears in sequences
- a(1) = 2; a(n+1) = a(n)-th composite.at n=37A022450
- G.f.: Product_{k>=1} (1 + 2*x^k).at n=35A032302
- Number of partitions satisfying (cn(0,5) = 0 and cn(1,5) <= cn(2,5) and cn(1,5) <= cn(3,5) and cn(4,5) <= cn(2,5) and cn(4,5) <= cn(3,5)).at n=53A036812
- Starting positions of strings of 3 0's in the decimal expansion of Pi.at n=14A050202
- a(n) is the starting position of the first occurrence of a string of at least n '0's in the decimal expansion of Pi.at n=4A050279
- Positive integers n such that phi(n) - d(n) = phi(n+1) - d(n+1) where d(n) is the number of divisors of n.at n=4A063069
- Numbers n such that d(n) = phi(n+1) - phi(n), where d(n) denotes the number of divisors of n.at n=5A066171
- Numbers n such that |phi(n+1)-phi(n)| = |d(n+1)-d(n)|, where phi is Euler's totient function and d(n) = number of divisors of n.at n=9A066219
- Starting positions of strings of four 0's in the decimal expansion of Pi.at n=1A083598
- Starting positions of strings of five 0's in the decimal expansion of Pi.at n=0A083599
- Index of first occurrence of exactly n consecutive zeros in a row in the decimal expansion of Pi.at n=4A096764
- Convolution square of A003106.at n=43A145468
- a(n) is obtained by applying the map k -> composite(k) n times, starting at n.at n=32A280327
- Expansion of 1/(1 - x/(1 - x^5/(1 - x^14/(1 - x^30/(1 - x^55/(1 - ... - x^(k*(k+1)*(2*k+1)/6)/(1 - ...))))))), a continued fraction.at n=38A295073
- Number of nX5 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0, 1 or 2 neighboring 1s.at n=2A297371
- T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0, 1 or 2 neighboring 1s.at n=23A297374
- Number of 3Xn 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0, 1 or 2 neighboring 1s.at n=4A297376
- Sum of the even parts in the partitions of n into 5 parts.at n=38A309547
- Number of separable partitions of n in which the number of distinct (repeatable) parts <= 4.at n=47A325713
- Numbers k such that phi(k) < phi(k+1) < phi(k+2) < phi(k+3) where phi is the Euler totient function (A000010).at n=39A327880