9800
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
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 26505
- Proper Divisor Sum (Aliquot Sum)
- 16705
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3360
- Möbius Function
- 0
- Radical
- 70
- Omega Function (Ω)
- 7
- 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
- 135
- 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
- yes
- Achilles Number
- yes
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- a(n)-th triangular number is a square: a(n+1) = 6*a(n) - a(n-1) + 2, with a(0) = 0, a(1) = 1.at n=6A001108
- a(n) = smallest number m such that for all k > m, either k or k+1 has a prime factor > prime(n).at n=4A002072
- Expansion of (1+x^2)/((1-x)^2*(1-x^2)^2).at n=47A005993
- Ruth-Aaron numbers (1): sum of prime divisors of n = sum of prime divisors of n+1.at n=18A006145
- a(n) = n*(n+1)*(2*n+1)/3.at n=24A006331
- a(n) = floor(n*(n-1)*(n-2)/12).at n=50A011894
- a(n) = 1*(n) + 2*(n-1) + 3*(n-2) + ... + (n+1-k)*k, where k = floor((n+1)/2).at n=47A023855
- a(n) = 1*(n+1-1) + 2*(n+1-2) + ... + k*(n+1-k), where k = floor((n+1)/2).at n=46A023856
- Triangle read by rows: T(n, k) = (k+1)*A132393(n+1, k+1), for 0 <= k <= n.at n=32A028421
- Erroneous version of A001108.at n=5A028443
- Coordination sequence for lattice D*_70 (with edges defined by l_1 norm = 1).at n=2A035820
- Coordination sequence for diamond structure D^+_70. (Edges defined by l_1 norm = 1.)at n=2A035911
- Number of partitions satisfying (cn(2,5) <= cn(1,5) and cn(3,5) <= cn(1,5) and cn(2,5) <= cn(4,5) and cn(3,5) <= cn(4,5)).at n=41A036802
- Expansion of 1/((1 - x)*(1 - 2*x - x^2)).at n=10A048739
- Values of n^2 - 1 resulting from A050795.at n=9A050799
- Number of primitive (aperiodic) word structures of length n using a 3-ary alphabet.at n=9A056274
- Number of primitive (aperiodic) palindromic structures using a maximum of three different symbols.at n=20A056477
- Numbers k such that k and k+1 are powerful numbers.at n=3A060355
- Powerful numbers of the form k^2 - 1.at n=3A060859
- a(n) = product of all even numbers between n-th prime and (n+1)-st prime.at n=24A061216