2019
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2696
- Proper Divisor Sum (Aliquot Sum)
- 677
- 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
- 1344
- Möbius Function
- 1
- Radical
- 2019
- 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
- 112
- 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
- Coordination sequence T1 for Zeolite Code AET.at n=31A008007
- Coordination sequence T2 for Zeolite Code AWW.at n=32A008046
- Expansion of Product_{m>=1} (1+q^m)^(-3).at n=26A022598
- a(n) = (n+3)^2 - 6.at n=42A028878
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 13.at n=22A031511
- Lucky numbers with size of gaps equal to 18 (upper terms).at n=12A031901
- Concatenation of 'nextprime(a(n)) and a(n)' and 'a(n) and nextprime(a(n))' are both prime.at n=48A034595
- Numbers k such that 17^k - 16 is prime.at n=5A034922
- Numbers n with property that, reading binary expansion of n from right to left, run lengths strictly increase.at n=47A037015
- Denominators of continued fraction convergents to sqrt(796).at n=7A042535
- The sequence e when b=[ 1,1,1,1,0,1,1,1,... ].at n=55A042959
- Numbers k such that 1 and 9 occur juxtaposed in the base-10 representation of k but not of k-1.at n=39A043232
- Numbers k such that 0 and 1 occur juxtaposed in the base-10 representation of k but not of k+1.at n=36A043996
- Numbers k such that 1 and 9 occur juxtaposed in the base-10 representation of k but not of k+1.at n=39A044012
- Numbers n such that string 4,3 occurs in the base 8 representation of n but not of n-1.at n=35A044222
- Numbers n such that string 8,3 occurs in the base 9 representation of n but not of n-1.at n=26A044326
- Numbers k such that string 1,9 occurs in the base 10 representation of k but not of k-1.at n=22A044351
- Numbers n such that string 4,3 occurs in the base 8 representation of n but not of n+1.at n=35A044603
- Numbers n such that string 8,3 occurs in the base 9 representation of n but not of n+1.at n=26A044707
- Numbers n such that string 0,1 occurs in the base 10 representation of n but not of n+1.at n=21A044714