7913
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
- 8148
- Proper Divisor Sum (Aliquot Sum)
- 235
- 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
- 7680
- Möbius Function
- 1
- Radical
- 7913
- 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
- 101
- 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
- Number of nonnegative solutions to x^2 + y^2 + z^2 <= n^2.at n=24A000604
- Numerators of central difference coefficients M_{3}^(2n+1).at n=7A002673
- Pseudoprimes to base 9.at n=45A020138
- Numbers k such that the continued fraction for sqrt(k) has period 27.at n=33A020366
- Number of ways to partition n elements into pie slices of different sizes of at least 2 allowing the pie to be turned over.at n=39A032230
- n satisfying sigma(n+1) = sigma(n-1).at n=17A055574
- Smallest multiple of 2n+1 with property that digits are odd and each digit is two more (mod 10) than the previous digit; or 0 if no such number exists.at n=20A062886
- Numbers k such that sigma(k-1) divides sigma(k+1).at n=21A067130
- Smallest available integer which fits into the repeating pattern 13579.at n=17A098758
- (L(n+2)+2*3^n)/5.at n=9A099164
- Greatest multiple of the n-th prime in A098962.at n=12A099620
- Last entry (and high point) in segment n of A079051.at n=33A117516
- Start with 1027 and repeatedly reverse the digits and add 16 to get the next term.at n=22A119455
- Members of A054591 that are not members of A121153.at n=40A135666
- a(n) = 4*n^2 + 4*n - 7.at n=43A166147
- a(n) = 12*n^2 - 8*n + 9.at n=25A167585
- Cubes (n * n * n) in carryless arithmetic mod 10.at n=37A169885
- Primitive numbers k such that m/k is in the Cantor set for some m.at n=46A173931
- Product of exactly two distinct primes congruent to 1 mod 8 (A007519).at n=26A185377
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>2n.at n=20A211644