2638
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3960
- Proper Divisor Sum (Aliquot Sum)
- 1322
- 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
- 1318
- Möbius Function
- 1
- Radical
- 2638
- 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
- 146
- 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
- yes
- Odd
- no
Appears in sequences
- Number of compositions of n into 4 ordered relatively prime parts.at n=24A000742
- a(n) = 4^n - 2*3^n.at n=6A002250
- Coordination sequence T7 for Zeolite Code MEL.at n=33A008156
- Population of "Triangle" cellular automaton at n-th generation.at n=27A018189
- Coordination sequence T1 for Zeolite Code IFR.at n=36A024982
- Numbers whose least quadratic nonresidue (A020649) is 13.at n=6A025025
- a(n) = floor(Sum_{1<=i<j<=n} (sqrt(j)-sqrt(i))^2).at n=35A025196
- Numbers k such that Hofstadter Q-sequence Q(k) (A005185) satisfies Q(k) = k/2.at n=33A027619
- 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 50.at n=12A031548
- Numbers with exactly five distinct base-7 digits.at n=32A031984
- Coordination sequence T3 for Zeolite Code CFI.at n=34A033601
- Coordination sequence T4 for Zeolite Code SBT.at n=41A033615
- Number of partitions of n into parts 5k+1 or 5k+2.at n=50A035371
- Numbers whose base-3 representation has exactly 8 runs.at n=28A043588
- Numbers n such that number of runs in the base 3 representation of n is congruent to 0 mod 8.at n=28A043798
- Numbers n such that number of runs in the base 3 representation of n is congruent to 8 mod 9.at n=28A043814
- Numbers k such that number of runs in the base 3 representation of k is congruent to 8 mod 10.at n=28A043823
- Numbers k such that the string 5,1 occurs in the base 9 representation of k but not of k-1.at n=36A044297
- Numbers n such that string 3,8 occurs in the base 10 representation of n but not of n-1.at n=29A044370
- Numbers n such that string 5,1 occurs in the base 9 representation of n but not of n+1.at n=36A044678