7207
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7208
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 7206
- Möbius Function
- -1
- Radical
- 7207
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 70
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 920
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 83.at n=31A031581
- Upper prime of a difference of 14 between consecutive primes.at n=36A031933
- Primes of form x^2 + 94*y^2.at n=48A033204
- Number of partitions of n such that cn(3,5) < cn(0,5) = cn(1,5) <= cn(2,5) = cn(4,5).at n=71A036875
- Primes with first digit 7.at n=37A045713
- a(n) = T(2n-1,n), array T given by A048225.at n=45A048234
- Primes at which the difference pattern X42Y (X and Y >= 6) occurs in A001223.at n=18A052164
- T(n,n-3), array T as in A054106.at n=34A054107
- Expansion of (1+x^2)*(1+x^5)/( Product_{j=1..7} (1-x^j) ).at n=33A060962
- A B_2 sequence: a(n) is the smallest prime such that the pairwise sums of distinct elements are all distinct.at n=40A062294
- Numbers k for which phi(prime(k)) is a square.at n=45A062325
- Primes starting and ending with 7.at n=10A062334
- Smallest prime with same leading digits as n!.at n=5A068844
- a(n) = Sum_{k=1..n} Sum_{d=1..k} (k mod d).at n=50A072481
- a(1) = 5; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=43A074340
- a(n) = floor(average of first n cubes).at n=29A078618
- Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <=6 (i.e., when d=2,4 or 6) and forming d-pattern=[4,2,6]; short d-string notation of pattern = [426].at n=6A078850
- Primes which when concatenated with their reverse and incremented by 2 yield a new prime.at n=39A088883
- Smallest prime equal to the sum of exactly 2n+1 distinct odd primes in at least n ways.at n=28A100697
- Primes from merging of 4 successive digits in decimal expansion of the Golden Ratio, (1+sqrt(5))/2.at n=3A103810