1917
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 2880
- Proper Divisor Sum (Aliquot Sum)
- 963
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1260
- Möbius Function
- 0
- Radical
- 213
- Omega Function (Ω)
- 4
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 55
- 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
- Number of restricted 3 X 3 matrices with row and column sums n.at n=28A005045
- List of pairs of primes in reverse order.at n=3A007797
- Year of birth of n-th President of U.S.A.at n=34A008745
- Expansion of (1+x^12)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=52A008773
- Coordination sequence T2 for Zeolite Code -ROG.at n=33A009860
- Numbers k such that k^2 is a sum of distinct factorials.at n=13A014597
- Odd numbers k such that phi(k) | sigma_3(k).at n=36A015809
- Numbers k such that phi(k + 11) | sigma(k).at n=41A015831
- Expansion of 1/(1-x^6-x^7-x^8-x^9-x^10-x^11-x^12-x^13-x^14-x^15-x^16).at n=40A017856
- Numbers with exactly 9 ones in binary expansion.at n=32A023691
- Number of 7's in all partitions of n.at n=30A024791
- Coordination sequence T4 for Zeolite Code MWW.at n=29A024989
- Coordination sequence T2 for Zeolite Code ITE.at n=30A027370
- For n odd, >1, not divisible by 3, we can write 3/n = 1/a + 1/b + 1/c with a>b>c>0, a,b,c distinct and odd; sequence gives smallest a.at n=22A027442
- For n != 1 mod 3, we can write 3/(2n+1) = 1/a + 1/b + 1/c with a>b>c>0, a,b,c distinct and odd; sequence gives smallest such a, or 1 if n = 1 mod 3.at n=34A027443
- Numbers k such that 51*2^k+1 is prime.at n=23A032375
- Numbers k such that 65*2^k+1 is prime.at n=25A032382
- Numbers k such that 203*2^k + 1 is prime.at n=12A032478
- Numbers in which all pairs of consecutive base-8 digits differ by 2.at n=48A033086
- Coordination sequence T3 for Zeolite Code SBT.at n=35A033614