1646
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
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2472
- Proper Divisor Sum (Aliquot Sum)
- 826
- 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
- 822
- Möbius Function
- 1
- Radical
- 1646
- 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
- 135
- 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 graphs with n nodes and floor(n(n-1)/4) edges.at n=7A000717
- Number of partitions of floor(7n/2)-1 into n nonnegative integers each no greater than 7.at n=12A001980
- Coordination sequence T2 for Zeolite Code DOH.at n=25A008079
- Triangle T(n,k) read by rows, giving number of graphs with n nodes (n >= 1) and k edges (0 <= k <= n(n-1)/2).at n=77A008406
- Number of ferrites M_8Y_n that repeat after 6n+40 layers.at n=12A011963
- Number of up steps in all length n left factors of Dyck paths.at n=10A014314
- a(n+1) is the smallest number > a(n) such that the digits of a(n)^2 are all (with multiplicity) contained in the digits of a(n+1)^2, with a(0)=1.at n=14A014563
- Expansion of 1/(1-x^9-x^10-x^11-x^12-x^13-x^14-x^15-x^16).at n=57A017883
- Expansion of (1+x^10)/((1-x)*(1-x^2)*(1-x^3)*(1-x^5)).at n=52A020702
- Numbers with exactly 5 2's in their ternary expansion.at n=26A023703
- a(n) = 3rd elementary symmetric function of {1, p(1), p(2), ..., p(n-1)}, where p(0) = 1.at n=3A024523
- a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-1)*a(1) for n >= 5, with initial values 1,1,2,1.at n=9A025271
- Number of partitions of n into an odd number of parts, the greatest being 5; also, a(n+9) = number of partitions of n+4 into an even number of parts, each <=5.at n=52A026925
- a(n) = n^2 + n + 6.at n=40A027691
- Q(sqrt(n)) has class number 3.at n=32A029703
- 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 40.at n=4A031538
- Numbers whose base-5 expansions have 5 distinct digits.at n=37A031946
- Numbers k such that 93*2^k+1 is prime.at n=22A032396
- Limit of the position of the n-th partition into parts 5k+1 or 5k+4 in the list of all integer partitions sorted in reverse lexicographic order, for integers == 0 (mod 5).at n=51A035405
- Number of partitions of n into parts not of form 4k+2, 20k, 20k+3 or 20k-3. Also number of partitions in which no odd part is repeated, with 1 part of size less than or equal to 2 and where differences between parts at distance 4 are greater than 1 when the smallest part is odd and greater than 2 when the smallest part is even.at n=39A036025