17720
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
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 39960
- Proper Divisor Sum (Aliquot Sum)
- 22240
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7072
- Möbius Function
- 0
- Radical
- 4430
- Omega Function (Ω)
- 5
- 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
- 123
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that 2*3^k + 1 is prime.at n=29A003306
- Numbers n such that 2*3^n + 1 is a primitive prime factor of 10^3^n - 1.at n=5A176351
- Number of (n+2) X (4+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 0 and no antidiagonal sum 3 and no row sum 1 and no column sum 1.at n=19A257443
- Expansion of phi(-x^3) * f(-x, -x^5) / psi(x) in powers of x where phi(), psi(), f(, ) are Ramanujan theta functions.at n=36A262614
- Number of n X 3 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.at n=20A281710
- Numbers k such that (13*10^k + 161)/3 is prime.at n=19A284779
- Number of binary enriched p-trees of weight n.at n=12A300443
- Number of partitions of n with rank a multiple of 3.at n=41A328988