16950
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 42408
- Proper Divisor Sum (Aliquot Sum)
- 25458
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4480
- Möbius Function
- 0
- Radical
- 3390
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- 110
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = 2*(2n-1)!!-(n-1)!*2^(n-1), where (2n-1)!! is A001147(n).at n=5A000779
- Number of protruded partitions of n with largest part at most 3.at n=16A005404
- Coordination sequence for {A_4}* lattice.at n=15A008531
- a(n) = (n+2)*(n+1)*(n^2 + 7*n - 12)/24.at n=22A014309
- a(1) = 1; a(n+1) = floor((sum{k=1 to n} a(k)^3)^(1/3)).at n=50A016085
- Partial sums of A038580.at n=19A086749
- Numbers n such that if p=prime(n), then p, p+6, p+12, p+18 are consecutive primes with p=6*k+5 for some k, where prime(n) denotes n-th prime.at n=28A090835
- Half the number of nX3 binary arrays with each element equal to at least two neighbors.at n=15A180752
- a(n) = 27*n^2 - 51*n + 24, n>=1.at n=25A304836
- Number of partitions of n into parts whose bitwise AND equals 0.at n=36A307435
- The number whose binary indices are the nontrivial divisors of n (greater than 1 and less than n).at n=29A328337
- Nonnegative numbers m such that if 2^k appears in the binary expansion of m, then k+1 divides m.at n=38A358970
- Number T(n,k) of partitions of [n] for which the difference between the longest and the shortest block size is k; triangle T(n,k), n>=0, 0<=k<=max(0,n-2), read by rows.at n=39A364971
- a(n) = Sum_{1 <= x_1, x_2, x_3 <= n} sigma( ( n/gcd(x_1, x_2, x_3, n) )^2 ).at n=5A373131