7909
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8640
- Proper Divisor Sum (Aliquot Sum)
- 731
- 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
- 7180
- Möbius Function
- 1
- Radical
- 7909
- 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
- 145
- 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
- Primitive repfigit numbers.at n=14A006576
- Repfigit (REPetitive FIbonacci-like diGIT) numbers (or Keith numbers).at n=16A007629
- Discriminants of quintic fields with 4 complex conjugates.at n=49A023685
- Potential Sierpiński numbers: integers for which the smallest m > 2^10 in A040076 such that n*2^m+1 is prime (A050921).at n=29A064721
- Numbers n such that A003313(n) = A003313(2n).at n=29A086878
- Numbers k such that the k-th prime is of the form 2*j^2 + 1.at n=30A090612
- Total number of nodes in all planted trees on n nodes.at n=10A095341
- Consider the family of multigraphs enriched by the species of linear order. Sequence gives the triangle read by rows giving coefficients of polynomials arising from enumeration of those multigraphs on n edges, arcs and loops.at n=16A098288
- Number of partitions of n into relatively prime parts such that multiplicities of parts are also relatively prime.at n=32A100953
- Partial sums of A102540 (primes that are not Chen primes).at n=29A115606
- Multiply-Add Recurrence Invariant (MARI) numbers.at n=30A121235
- Keith numbers together with the numbers from 0 through 9.at n=26A130010
- Products (semiprimes) of two distinct double-safe primes.at n=7A157356
- Number of binary strings of length n with no substrings equal to 0000 0010 or 1001.at n=12A164421
- Triangle in which row n has n semiprimes such that (p+1)(q+1) is the same for each semiprime pq and (p+1)(q+1) is as small as possible.at n=38A180333
- A list of 63 distinct numbers such that the sum of their reciprocals is 1 and each number is of the form p*q where p and q are distinct primes.at n=62A201464
- Number of n-digit 8th powers.at n=35A216658
- Semiprimes which are the arithmetic mean of three consecutive primes.at n=32A242218
- Number of (undirected) paths in the m X n king graph (triangle read by rows with m = 1..n and n = 1..).at n=11A307026
- Number of (undirected) paths in the 2 X n king graph.at n=4A339750