2426
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3642
- Proper Divisor Sum (Aliquot Sum)
- 1216
- 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
- 1212
- Möbius Function
- 1
- Radical
- 2426
- 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
- 45
- 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
- a(1)=0; for n>1, a(n) = number of isomeric hydrocarbons of the acetylene series with carbon content n.at n=12A000642
- Numbers k such that phi(k) = phi(k+2).at n=39A001494
- Number of partitions of n into parts 2, 3, 4, 5, 6, 7.at n=55A001996
- Coordination sequence T2 for Zeolite Code PAU.at n=36A008220
- Table T(n,k), n>=0 and k>=0, read by antidiagonals: the k-th column given by the k-th Narayana polynomial.at n=60A008550
- Coordination sequence T5 for Zeolite Code VET.at n=30A009906
- a(n) = floor(n(n-1)(n-2)(n-3)/18).at n=16A011928
- Numbers k such that the continued fraction for sqrt(k) has period 13.at n=14A020352
- Expansion of 1/((1-x)(1-5x)(1-6x)(1-7x)).at n=3A022033
- Index of 5^n within sequence of numbers of form 2^i * 5^j.at n=45A022334
- a(n) = floor(Sum_{1<=i<j<=n} (sqrt(j)-sqrt(i))^2).at n=34A025196
- Number of partitions of n into distinct parts, the least being even.at n=56A026833
- Concatenation of n and n + 2 or {n,n+2}.at n=23A032607
- Even numbers k such that b(k) is greater than b(k-1) and b(k+1); b(k) = A033178(k).at n=37A038007
- Numbers k such that the string 8,5 occurs in the base 9 representation of k but not of k-1.at n=32A044328
- Numbers n such that string 2,6 occurs in the base 10 representation of n but not of n-1.at n=27A044358
- Numbers n such that string 8,5 occurs in the base 9 representation of n but not of n+1.at n=32A044709
- Numbers n such that string 2,6 occurs in the base 10 representation of n but not of n+1.at n=27A044739
- Nonprime numbers n such that n and n-reversed (<>n and no leading zeros) have the same number of prime factors and these prime factors (palindromes allowed here) are also reversals of each other.at n=29A050702
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 13.at n=7A051978