2627
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2736
- Proper Divisor Sum (Aliquot Sum)
- 109
- 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
- 2520
- Möbius Function
- 1
- Radical
- 2627
- 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
- 27
- 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
- Perrin sequence (or Perrin numbers, or Ondrej Such sequence): a(n) = a(n-2) + a(n-3) with a(0) = 3, a(1) = 0, a(2) = 2.at n=28A001608
- a(n) = n concatenated with n + 1.at n=25A001704
- f-vectors for simplicial complexes of dimension at most 1 (graphs) on at most n-1 vertices.at n=25A011826
- a(n) = n*(2*n-3).at n=37A014107
- a(n) = [ a(n-1)/a(1) + a(n-2)/a(2) + ... + a(1)/a(n-1) ], for n >= 3.at n=17A022863
- Pair up the numbers.at n=13A030656
- Numbers k such that 237*2^k+1 is prime.at n=11A032495
- a(n) = (2*n+1) * (4*n-1).at n=18A033566
- Concatenation of two or more consecutive positive integers.at n=34A035333
- Positive numbers having the same set of digits in base 5 and base 7.at n=39A037430
- Number of partitions satisfying cn(1,5) + cn(4,5) <= cn(2,5) and cn(1,5) + cn(4,5) <= cn(3,5).at n=36A039876
- Denominators of continued fraction convergents to sqrt(619).at n=7A042189
- a(n) = (s(n) + 1)/5, where s(n) = n-th base-5 palindrome that starts with 4.at n=42A043053
- Numbers k such that the string 3,8 occurs in the base 9 representation of k but not of k-1.at n=36A044286
- Numbers n such that string 2,7 occurs in the base 10 representation of n but not of n-1.at n=29A044359
- Numbers n such that string 3,8 occurs in the base 9 representation of n but not of n+1.at n=36A044667
- Numbers n such that string 5,3 occurs in the base 9 representation of n but not of n+1.at n=35A044680
- Numbers n such that string 2,7 occurs in the base 10 representation of n but not of n+1.at n=29A044740
- Expansion of g.f. (1 - 4*x + 6*x^2 - 2*x^3)/((1-x)^3*(1-2*x)^2).at n=8A048503
- Composite numbers n such that k! == 1 (mod n) for some k > 2.at n=12A049048