2637
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 3822
- Proper Divisor Sum (Aliquot Sum)
- 1185
- 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
- 1752
- Möbius Function
- 0
- Radical
- 879
- 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
- 53
- 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
- no
- Odd
- yes
Appears in sequences
- Number of series-reduced planted trees with n+9 nodes and 4 internal nodes.at n=17A001860
- Number of equivalence classes of binary sequences of period n.at n=18A002729
- Numbers that are the sum of 12 positive 6th powers.at n=43A003368
- a(n) = Fibonacci(n+2) + prime(n).at n=15A004399
- Number of non-Abelian metacyclic groups of order 2^n.at n=45A007982
- Apply partial sum operator twice to binary rooted tree numbers.at n=12A014168
- Numbers k such that Fib(k) == -34 (mod k).at n=21A023169
- A036827/2.at n=5A036828
- Base-8 palindromes that start with 5.at n=11A043025
- Numbers n such that string 5,0 occurs in the base 9 representation of n but not of n-1.at n=36A044296
- Numbers n such that string 5,5 occurs in the base 9 representation of n but not of n-1.at n=32A044301
- Numbers n such that string 3,7 occurs in the base 10 representation of n but not of n-1.at n=29A044369
- Numbers n such that string 5,0 occurs in the base 9 representation of n but not of n+1.at n=36A044677
- Numbers n such that string 3,7 occurs in the base 10 representation of n but not of n+1.at n=29A044750
- a(1) = 4; a(n) is smallest number >= a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=26A046254
- Numbers k such that k and k-1 both have 6 divisors.at n=32A049104
- Restricted partitions.at n=18A049285
- a(n)=T(n,1), array T as in A049735.at n=29A049744
- Sequence A001033 gives the numbers n such that the sum of the squares of n consecutive odd numbers x^2 + (x+2)^2 + ... +(x+2n-2)^2 = k^2 for some integer k. For each n, this sequence gives the least value of x.at n=24A056131
- Sum of a(n) terms of 1/k^(2/3) first exceeds n.at n=39A056178