2219
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2544
- Proper Divisor Sum (Aliquot Sum)
- 325
- 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
- 1896
- Möbius Function
- 1
- Radical
- 2219
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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
- Number of restricted hexagonal polyominoes with n cells.at n=7A002212
- Number of polyhexes with n hexagons, having reflectional symmetry (see Harary and Read for precise definition).at n=13A002215
- Numerators of continued fraction convergents to cube root of 7.at n=6A005484
- Coordination sequence T4 for Zeolite Code DFO.at n=36A009878
- Coordination sequence T1 for Zeolite Code RUT.at n=31A009897
- Coordination sequence T1 for Zeolite Code IFR.at n=33A024982
- s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n-k+1), where k = [ n/2 ], s = (composite numbers).at n=17A025102
- a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-2)*a(2) for n >= 3.at n=7A025238
- a(n) = (1/2)*s(n+3), where s = A025248.at n=10A025249
- (d(n)-r(n))/2, where d = A008778 and r is the periodic sequence with fundamental period (1,1,0,1).at n=26A026052
- Fractional part of square root of a(n) starts with 1: first term of runs.at n=44A034107
- Number of partitions of n with equal nonzero number of parts congruent to each of 0 and 2 (mod 4).at n=36A035547
- Number of partitions satisfying cn(1,5) <= cn(2,5) + cn(3,5) and cn(4,5) <= cn(2,5) + cn(3,5).at n=28A039890
- Numerators of continued fraction convergents to sqrt(924).at n=4A042786
- a(n)=(s(n)+4)/8, where s(n)=n-th base 8 palindrome that starts with 4.at n=39A043068
- Numbers having four 2's in base 4.at n=38A043344
- Numbers whose base-13 representation has exactly 4 runs.at n=8A043659
- Catafusenes (see reference for precise definition).at n=13A044044
- Numbers n such that string 5,3 occurs in the base 8 representation of n but not of n-1.at n=38A044230
- Numbers n such that string 3,5 occurs in the base 9 representation of n but not of n-1.at n=30A044283