2891
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 3420
- Proper Divisor Sum (Aliquot Sum)
- 529
- 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
- 2436
- Möbius Function
- 0
- Radical
- 413
- 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
- 48
- 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
- a(n) = (12*n+1)*(12*n+11).at n=4A001538
- a(n) = ceiling(1000*log(n)).at n=17A004242
- Number of matched trees with 2n nodes.at n=8A005751
- Generalized Lucas numbers.at n=12A006491
- Coordination sequence T4 for Zeolite Code -CLO.at n=47A009853
- Expansion of 1/(1 - x^10 - x^11 - x^12 - x^13 - x^14 - x^15 - x^16).at n=69A017892
- Expansion of 1/((1-x)(1-2x)(1-6x)(1-10x)).at n=3A021202
- Define the sequence T(a_0,a_1) by a_{n+2} is the greatest integer such that a_{n+2}/a_{n+1}<a_{n+1}/a_n for n >= 0. This is T(8,57).at n=3A022038
- Numbers k that divide the (left) concatenation of all numbers <= k written in base 8 (most significant digit on left).at n=13A029477
- Cycle-path coverings of a family of digraphs.at n=8A030236
- Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 2,3,1,0.at n=5A037751
- Number of partitions satisfying cn(0,5) + cn(2,5) + cn(3,5) <= 1.at n=42A039853
- Numbers k such that the string 6,2 occurs in the base 9 representation of k but not of k-1.at n=39A044307
- Numbers n such that string 9,1 occurs in the base 10 representation of n but not of n-1.at n=30A044423
- Numbers m such that string 9,1 occurs in the base 10 representation of m but not of m+1.at n=30A044804
- Numbers whose base-3 representation contains exactly three 0's and four 2's.at n=32A045008
- a(n) = (s(n)-(n mod 2)) / n where s(n) is A006533.at n=42A056891
- (tau<=)_6(n).at n=39A061204
- Composite numbers whose sum of aliquot divisors as well as product of aliquot divisors is a perfect square.at n=35A064116
- Nonprime numbers n such that the sum of aliquot divisors of n (A001065) and product of aliquot divisors of n (A048741) are both perfect squares.at n=36A064121