9316
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 17388
- Proper Divisor Sum (Aliquot Sum)
- 8072
- 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
- 4352
- Möbius Function
- 0
- Radical
- 4658
- 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
- yes
- 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
- 153
- 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
- Doubly triangular numbers: a(n) = n*(n+1)*(n^2+n+2)/8.at n=16A002817
- High temperature series for spin-1/2 Ising surface susceptibility on square lattice.at n=6A003489
- a(n) = p*(p-1)/2 for p = prime(n).at n=32A008837
- Aliquot sequence starting at 180.at n=42A008891
- a(n) = 2*n*(4*n + 1).at n=34A033585
- Triangular numbers that have some nontrivial permutation of digits which is also triangular.at n=36A034291
- Increasing gaps among twin primes: size.at n=43A036063
- Centered 9-gonal (also known as nonagonal or enneagonal) numbers. Every third triangular number, starting with a(1)=1.at n=45A060544
- a(n) = 49*(n*(n+1)/2) + 6.at n=19A061792
- Largest triangular number less than or equal to sum of previous terms with a(0)=1.at n=15A061883
- Smallest triangular number that contains the string n in its exact center.at n=31A062690
- Smallest triangular numbers that contain the digits of n anywhere in their middle.at n=31A062829
- Numbers that define integer Heronian triangles [a(n), prime(a(n)), A068968(n)] with area A068969(n).at n=31A068967
- Smallest triangular number with value of the internal digits = n; or 0 if no such number exists.at n=31A069692
- Nested floor product of n and fractions (k+1)/k for all k>0 (mod 4), divided by 4.at n=21A073361
- Triangular numbers which are the sum of two squares.at n=22A073613
- Triangular numbers which are 4-almost primes.at n=37A076578
- Nearest integer to Sum_{k=0..n} binomial(n,k)/2^(k*(k-1)/2).at n=50A079492
- Sort the digits of these triangular numbers into descending order and drop zeros to get primes.at n=17A082923
- p such that p^4 + q^4 = r^4 + s^4 = a(n).at n=31A088728