2228
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
- 6
- Divisor Sum
- 3906
- Proper Divisor Sum (Aliquot Sum)
- 1678
- 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
- 1112
- Möbius Function
- 0
- Radical
- 1114
- Omega Function (Ω)
- 3
- 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
- 45
- 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 phi(2k-1) < phi(2k), where phi is Euler's totient function A000010.at n=31A001836
- a(n) = 1 + Sum_{i=1..n} (n-i+1)*phi(i).at n=27A005598
- Coordination sequence T1 for Zeolite Code BRE.at n=31A008058
- Coordination sequence T3 for Zeolite Code MEP.at n=28A008159
- Coordination sequence T5 for Zeolite Code DFO.at n=36A009879
- a(n) = floor(n*(n-1)*(n-2)/7).at n=26A011889
- Fibonacci sequence beginning 4, 13.at n=12A022132
- Numbers k such that Fibonacci(k) == -3 (mod k).at n=30A023164
- a(n) = b(n) + d(n), where b(n) = (n-th Lucas number > 1) and d(n) = (n-th non-Lucas number).at n=14A023493
- Index of 10^n within the sequence of the numbers of the form 4^i*10^j.at n=51A025742
- Congruence classes of triangles which can be drawn using lattice points in n X n grid as vertices.at n=10A028419
- 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 22.at n=43A031520
- Numbers k such that 253*2^k+1 is prime.at n=28A032503
- Concatenation of n and n + 6 or {n,n+6}.at n=21A032611
- Numbers whose maximal base-10 run length is 3.at n=36A033284
- Fractional part of square root of a(n) starts with 2: first term of runs.at n=44A034108
- Coefficients of completely replicable function 50a with a(0) = 1.at n=46A034320
- Even numbers k such that b(k) is greater than b(k-1) and b(k+1); b(k) = A033178(k).at n=34A038007
- Coordination sequence T4 for Zeolite Code SFF.at n=31A038434
- Number of partitions satisfying cn(1,5) <= 1 and cn(4,5) <= 1.at n=34A039854