1810
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 3276
- Proper Divisor Sum (Aliquot Sum)
- 1466
- 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
- 720
- Möbius Function
- -1
- Radical
- 1810
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 68
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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(n) = sigma_2(n): sum of squares of divisors of n.at n=37A001157
- a(n) = Sum_{k = 0..n} binomial(n,k)^4.at n=4A005260
- Number of paraffins.at n=18A005997
- Numbers k such that k*3^k - 1 is prime.at n=12A006553
- Coordination sequence T2 for Zeolite Code AEL.at n=28A008005
- Coordination sequence T2 for Zeolite Code CON.at n=30A009869
- Coordination sequence T5 for Zeolite Code CON.at n=30A009872
- [ sqrt(3/2)^n ].at n=37A014215
- From the game of Mousetrap.at n=7A018934
- Numbers k such that the continued fraction for sqrt(k) has period 19.at n=13A020358
- a(n) = n*(9*n + 1)/2.at n=20A022267
- Ordered sequence of distinct terms of the form floor(x^i * floor(x^j)), where x = sqrt(2).at n=61A022768
- Numbers k such that Fibonacci(k) == 55 (mod k).at n=29A023181
- Coordination sequence T3 for Zeolite Code MWW.at n=28A024988
- Position of numbers of form 3*n^2 in A025060 (numbers of form j*k + k*i + i*j, where 1 <=i < j < k).at n=21A025064
- a(n) = Sum_{k=0..n} (k+1) * A026626(n,k).at n=8A026965
- Number of partitions of n into an even number of parts, the least being 5; also, a(n+5) = number of partitions of n into an odd number of parts, each >=5.at n=62A027197
- a(n) = n^2 + n + 4.at n=42A027689
- Number of ways to partition n elements into pie slices each with an odd number of elements.at n=21A032189
- Number of cyclic compositions of n into parts >= 2.at n=21A032190