7501
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8092
- Proper Divisor Sum (Aliquot Sum)
- 591
- 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
- 6912
- Möbius Function
- 1
- Radical
- 7501
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 176
- 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
- Restricted partitions.at n=17A002573
- Pseudoprimes to base 24.at n=30A020152
- Pseudoprimes to base 57.at n=40A020185
- Strong pseudoprimes to base 24.at n=9A020250
- Strong pseudoprimes to base 57.at n=9A020283
- Numbers k such that the continued fraction for sqrt(k) has period 73.at n=3A020412
- Least m such that if r and s in {1/1, 1/4, 1/9,..., 1/n^2} satisfy r < s, then r < k/m < s for some integer k.at n=27A024827
- Numbers whose set of base-12 digits is {1,4}.at n=26A032824
- Numbers each of whose runs of digits in base 12 has length 2.at n=45A033010
- Positive numbers having the same set of digits in base 6 and base 9.at n=34A037436
- Numerators of continued fraction convergents to sqrt(186).at n=9A041344
- Numerators of continued fraction convergents to sqrt(744).at n=9A042432
- Rhombi (in 3 different orientations) in a rhombus with 60-degree acute angles.at n=25A052153
- Write fundamental unit for real quadratic field of discriminant n as x + y*omega; sequence gives values of x for n == 2 mod 4.at n=38A053371
- Column 7 of triangle A055907.at n=5A055913
- 5-morphic but not bimorphic, automorphic nor trimorphic.at n=39A056036
- Composite n such that (n-1)*phi(n) is a perfect square.at n=16A069953
- a(1)=1, a(n) is the smallest integer > a(n-1) such that the largest element in the simple continued fraction for S(n)=1/a(1)+1/a(2)+...+1/a(n) equals 3n.at n=37A070899
- Reverse of smallest prime factor of k = largest prime factor of k+1; a(1)=1.at n=8A071392
- Expansion of (1+x^3*C^2)*C^4, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.at n=7A071733