4431
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 6784
- Proper Divisor Sum (Aliquot Sum)
- 2353
- 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
- 4431
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 121
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = (n+1)*(n^2+n+2)/2; g.f.: (1 + 2*x^2) / (1 - x)^4.at n=20A006000
- Coordination sequence T2 for Zeolite Code MOR.at n=43A008183
- Coordination sequence T1 for Zeolite Code AHT.at n=45A009866
- Number of (unordered) triples of integers from [1,n] with no common factors between pairs.at n=44A015617
- Pseudoprimes to base 55.at n=26A020183
- Pseudoprimes to base 71.at n=31A020199
- 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 44.at n=20A031542
- Lucky numbers with size of gaps equal to 18 (upper terms).at n=24A031901
- G.f. satisfies A(x) = 1 + x*cycle_index(G,A(x)) where G = cyclic group of order 41 generated by (1,2,...,41).at n=5A036737
- Coordination sequence T8 for Zeolite Code SFF.at n=44A038435
- Coordination sequence T2 for Zeolite Code DON.at n=45A047954
- 2-ranks of difference sets constructed from Glynn type I hyperovals.at n=13A049112
- 23-gonal numbers: a(n) = n(21n-19)/2.at n=21A051875
- a(n) = 10*n^2+n.at n=20A055437
- Positive numbers whose product of digits is four times their sum.at n=43A062036
- Limit of A069258(k,n) = number of partitions of 2*k into k-n prime parts, as k tends to infinity.at n=33A069259
- a(1) = 8; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=36A074344
- Number of simple graphs g on n nodes with |Aut(g)| = 2.at n=7A075095
- Sums of terms of groups in A075626.at n=20A075629
- Numbers k such that 7*10^k + 9 is prime.at n=24A097954