9731
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10032
- Proper Divisor Sum (Aliquot Sum)
- 301
- 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
- 9432
- Möbius Function
- 1
- Radical
- 9731
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 47
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- Third row of Pascal-(1,4,1) array A081579.at n=28A081587
- Counterexamples to the conjecture that an even, prime-indexed triangular plus 1 equals a prime or that an odd, prime-indexed triangular minus 2 equals a prime.at n=11A097785
- A puzzle: reverse digits of n^2 + 10.at n=37A097990
- A puzzle: reverse digits of n^2 + 10.at n=37A097991
- Where records occur in A111390.at n=43A114111
- Odd digits in decreasing order.at n=27A119252
- Binomial transform of A001113.at n=11A126082
- Apply partial sum operator twice to sequence of squares of the first n primes.at n=10A157492
- The smallest magic constant of an n X n magic square with distinct prime entries.at n=12A164843
- a(n) = 8*n^2 - 2*n + 1.at n=35A185438
- Positions of primes within Dana Scott's sequence (A048736).at n=21A192242
- Number of n X n 0..3 arrays with rows and columns unimodal and antidiagonals nondecreasing.at n=2A224044
- Number of nX3 0..3 arrays with rows and columns unimodal and antidiagonals nondecreasing.at n=2A224045
- T(n,k)=Number of nXk 0..3 arrays with rows and columns unimodal and antidiagonals nondecreasing.at n=12A224050
- Irregular array read by rows in which row n lists the positive integers k in ascending order for which 1 is in a primitive cycle of n positive integers under iteration by the Collatz-like 3x+k function.at n=45A226618
- Number of partitions p of n such that (sum of parts with multiplicity 1) <= (sum of all other parts).at n=36A240449
- Non-repunit elements of A261020 in nonincreasing order.at n=15A261322
- Number of peaks in all bargraphs having semiperimeter n (n>=2).at n=9A271941
- Take a squarefree semiprime and take the difference of its prime factors. If it is a squarefree semiprime repeat the process. Sequence lists the squarefree semiprimes that generate other squarefree semiprimes only in the first k steps of this process. Case k = 4.at n=19A296811
- Number of integer partitions of n whose number of submultisets is less than or equal to n.at n=48A325834