4615
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
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 6048
- Proper Divisor Sum (Aliquot Sum)
- 1433
- 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
- 3360
- Möbius Function
- -1
- Radical
- 4615
- 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
- 90
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = (8*n+1)*(8*n+7).at n=8A001533
- 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 13.at n=38A031511
- Numbers n such that s(n)+s(n+1)+...+s(n+10) = t(n)+t(n+1)+...+t(n+10).at n=5A033915
- a(n) = Sum_{k=1..floor(n/2)} T(n, 2k), array T as in A049777.at n=28A049779
- Numerators in expansion of Euler transform of b(n) = 1/4.at n=5A061161
- Numbers k such that floor(k*e) is a square.at n=44A062268
- Numbers k such that sigma(k) divides sigma(phi(k)).at n=24A066831
- Numbers n such that sigma(phi(n))/sigma(n) = 2.at n=16A067382
- a(n) = floor((n+2)^(n+2)/n^n).at n=24A078111
- Least positive integer multiples of angle x such that their direction cosines form a unit vector: Sum_{k>0} cos(a(k)*x)^2 = 1, where a(1)=1, a(n+1)>a(n) and x=3-Pi/2.at n=20A080139
- Greedy frac multiples of 1/Pi: a(1)=1, Sum_{n>0} frac(a(n)*x) = 1 at x=1/Pi, where "frac(y)" denotes the fractional part of y.at n=19A080142
- Numbers n such that ((n-1)^2+1)/2 and n^2+1 and ((n+1)^2+1)/2 are prime if n is even or (n-1)^2+1 and (n^2+1)/2 and (n+1)^2+1 are prime if n is odd.at n=25A082612
- a(n) = number of primes of the form x^2 + 1 <= 2^n.at n=31A083847
- Numbers k such that 7^k + 6^(k-1) is prime.at n=18A096185
- a(n) = Sum_{k=0..floor(n/6)} C(n-3k,3k) * 2^k.at n=18A100135
- Numbers k such that k^4 + 4 is semiprime.at n=43A108814
- G.f. satisfies: A(x) = 1/(1-x) * A(x^2)*A(x^3)*A(x^4)*...*A(x^n)*...at n=22A129374
- Numbers n where |sinc(n)| decreases monotonically to 0 (where sinc(x)=sin(x)/x).at n=38A131975
- List of pairs (n,m) with n < m such that the decimal expansion of m is a cyclic shift of that of n and m^2 is a cyclic shift of n^2.at n=6A134514
- First elements of the pairs listed in A134514.at n=3A134584