16225
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 22320
- Proper Divisor Sum (Aliquot Sum)
- 6095
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11600
- Möbius Function
- 0
- Radical
- 3245
- Omega Function (Ω)
- 4
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 159
- 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
- Convolution of A000201 with itself.at n=32A023663
- a(n) = T(n, 2*n-6), T given by A027960.at n=13A027968
- McKay-Thompson series of class 30B for the Monster group with a(0) = 0.at n=36A058613
- Diagonal in array of n-gonal numbers A081422.at n=24A081437
- Number of pairs with two different elements which can be obtained by selecting unique elements from two sets with n+1 and n^2 elements respectively and n common elements.at n=25A085490
- Seaweeds(n): number of n-step self-avoiding walks on upper two quadrants grid starting at origin.at n=10A116903
- Ulam's spiral (ENE spoke).at n=32A143856
- a(n) = 676*n + 1.at n=23A158386
- a(n) = 24*n^2 + 1.at n=26A158547
- a(n) = (4*n + 3)*(1 + 2*n^2)/3.at n=18A168574
- a(n) = (4*n^3 - 6*n^2 + 8*n + 9 + 3*(-1)^n)/12.at n=37A168582
- a(n) = n*(n+1)*(9*n^2 - n - 5)/6.at n=10A172075
- a(n) = n*(n^3+n^2+2*n+1).at n=11A186636
- Number of nXnXn 0..6 triangular arrays with each element x equal to the number its neighbors equal to 1,3,2,1,2,0,0 for x=0,1,2,3,4,5,6.at n=6A205082
- Number of 4-bead necklaces labeled with numbers -n..n not allowing reversal, with sum zero and first differences in -n..n.at n=35A208995
- Numbers k such that the average of the divisors of k and k+1 is the same.at n=10A238380
- Number of partitions of n having no perfect cube parts (n>=0).at n=48A264393
- Numbers n such that the decimal number concat(6,n) is a square.at n=29A273361
- a(n) = 2*A090495(n) - 1.at n=28A274297
- Numbers m such that m^2+1 is semiprime with (m-1)^2+1 and (m+1)^2+1 primes.at n=31A321985