7206
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 14424
- Proper Divisor Sum (Aliquot Sum)
- 7218
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 2400
- Möbius Function
- -1
- Radical
- 7206
- Omega Function (Ω)
- 3
- 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
- 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
- 163
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Walks on hexagonal lattice using each point at most twice.at n=5A007274
- Shifts 4 places right under binomial transform.at n=11A010742
- Shifts 4 places left under inverse binomial transform.at n=15A010743
- Katadromes: digits in base 6 are in strict descending order.at n=57A023788
- Base-7 palindromes that start with 3.at n=16A043017
- Number of 2 X 2 matrices with elements from {0,1,2,...,n} and with Nim-Determinant 1. (The Nim-Determinant of the 2 X 2 matrix [a,b; c,d] is defined to be a*d xor b*c, where * denotes Nim-Multiplication.)at n=29A059954
- Generalized Catalan numbers C(-5; n).at n=5A064327
- Triangle composed of generalized Catalan numbers.at n=60A064334
- Binomial transform of A007318 (Pascal's triangle by rows).at n=12A106462
- a(n) = a(n-1) + a(n-3) + a(n-4), n >= 4, with initial terms 1,-1,2,3.at n=20A111574
- Column 0 of the matrix 5th power of triangle A167015.at n=5A167145
- Numbers k such that k^3 +-7 are primes.at n=23A176685
- Number of disconnected regular simple graphs on n vertices with girth at least 5.at n=30A185215
- Volume of Johnson square pyramid placed upright on cube (rounded down) with edge lengths equal to n.at n=17A227221
- Initial members of abundant quadruplets, i.e., values of k such that (k, k+2, k+4, k+6) are all abundant numbers.at n=16A231089
- Number of binary sequences of length n that contain at least one contiguous subsequence 011.at n=13A232580
- Positive integers m with p(m)^2 + q(m)^2 prime, where p(.) is the partition function (A000041) and q(.) is the strict partition function (A000009).at n=47A236413
- a(n) = 10^(prime(n)-1) mod prime(n)^2.at n=31A265012
- Number of partitions of n having no even singletons.at n=39A265254
- Numbers k such that k - 13, k + 1, k + 5, k + 7, and k + 13 are all prime.at n=4A281937