2882
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 4752
- Proper Divisor Sum (Aliquot Sum)
- 1870
- 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
- 1300
- Möbius Function
- -1
- Radical
- 2882
- 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
- yes
- 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
- 141
- 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
- Pentagonal numbers: a(n) = n*(3*n-1)/2.at n=44A000326
- Palindromic pentagonal numbers.at n=5A002069
- Number of 4-line partitions of n (i.e., planar partitions of n with at most 4 lines).at n=14A002799
- Pentagonal numbers written backwards.at n=44A004163
- a(n) = least integer m > a(n-1) such that m - a(n-1) != a(j) - a(k) for all j, k less than n; a(1) = 1, a(2) = 2.at n=50A004978
- a(n) = 5^n - 3^n.at n=5A005058
- Quadrinomial coefficients.at n=9A005719
- Coordination sequence T2 for feldspar.at n=36A008255
- Number of points on the surface of 5-dimensional cube.at n=4A008512
- Coordination sequence for CaF2(1), F position.at n=18A009924
- Coordination sequence for CaF2(2), F position.at n=24A009925
- a(0) = 1, a(n) = 5*n^2 + 2 for n>0.at n=24A010001
- a(0) = 1, a(n) = 20*n^2 + 2 for n>0.at n=12A010010
- Even pentagonal numbers.at n=22A014633
- Strobogrammatic numbers: numbers that are the same upside down (using calculator-style numerals).at n=53A018846
- Positive numbers k such that k = x^5 + y^5 has a solution in nonzero integers x, y.at n=17A020896
- a(n) = (prime(n)^2 - 1)/24.at n=53A024702
- a(n) = least m such that if r and s in {1/1, 1/4, 1/7, ..., 1/(3n-2)} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=24A024836
- a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026681.at n=5A026987
- 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 52.at n=13A031550