7566
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 16464
- Proper Divisor Sum (Aliquot Sum)
- 8898
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2304
- Möbius Function
- 1
- Radical
- 7566
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 132
- 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
- Coordination sequence for NiAs(2), As position.at n=41A009945
- Coordination sequence for NiAs(2), Ni position.at n=41A009946
- Fibonacci sequence beginning 4, 30.at n=13A022387
- Least k such that the first k terms of the Kolakoski sequence (A000002) contain n more 2's than 1's.at n=9A025503
- a(n) = (d(n)-r(n))/2, where d = A026043 and r is the periodic sequence with fundamental period (1,1,0,0).at n=32A026044
- a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n-1 <= 2^(p+1), with a(1) = 1, a(2) = 3, and a(3) = 1.at n=13A049964
- Smallest multiple of (n+1)-st prime which is == 1 mod n-th prime.at n=23A073604
- Ordered product of the sides of primitive Pythagorean triangles divided by 60.at n=18A081752
- Convolution of sigma(n) with phi(n).at n=33A086733
- a(n) = a(n-1) + 6*a(n-2), a(0)=1, a(1)=0.at n=9A102901
- Numbers k such that phi(k)*sigma(k) is a cube.at n=8A114077
- The largest part summed over all partitions of n in which every integer from the smallest part to the largest part occurs.at n=40A117469
- "666" in bases 7 and higher rewritten in base 10.at n=28A121205
- Left border of triangle A137629.at n=27A137631
- Values of n such that n^a-+a are primes, a=5.at n=7A155021
- a(n) = 9*n^2 - 3.at n=28A157872
- 6 times centered hexagonal numbers: 18*n*(n+1) + 6.at n=20A164016
- Number of permutations of length n which avoid the patterns 4231 and 4123.at n=8A165542
- Numbers that are repdigits with length > 2 in more than one base.at n=21A167783
- G.f. satisfies: A(x) = (1 + x*A(2x))^3.at n=4A171201