7500
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 30
- Divisor Sum
- 21868
- Proper Divisor Sum (Aliquot Sum)
- 14368
- 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
- 2000
- Möbius Function
- 0
- Radical
- 30
- Omega Function (Ω)
- 7
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 176
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- yes
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Index of (the image of) the modular group Gamma(n) in PSL_2(Z).at n=24A001766
- a(n) = n*(n+1)^2/2.at n=24A006002
- Trails of length n on square lattice.at n=8A006817
- Expansion of 1/((1-4x)(1-5x)(1-8x)(1-11x)).at n=3A028122
- Expansion of (theta_3(z)*theta_3(11z) + theta_2(z)*theta_2(11z))^3.at n=47A028611
- Numbers k such that A174141(k) is divisible by k.at n=35A032581
- Base-7 palindromes that start with 3.at n=22A043017
- Numbers whose base-3 representation has exactly 9 runs.at n=30A043589
- Numbers n such that number of runs in the base 3 representation of n is congruent to 0 mod 9.at n=30A043806
- Numbers k such that number of runs in the base 3 representation of k is congruent to 9 mod 10.at n=30A043824
- Number of factorizations into distinct factors with 3 levels of parentheses indexed by prime signatures. A050349(A025487).at n=32A050350
- Numbers k such that phi(k) = phi(k - phi(k)).at n=35A051487
- a(n) = (5*n+10)(!^5)/10(!^5), related to A052562 ((5*n)(!^5) quintic, or 5-factorials).at n=3A051691
- Least k for which the integers Floor(k/m^2) for m=1,2,...,n are distinct.at n=28A054062
- Saint-Exupéry numbers: ordered products of the three sides of Pythagorean triangles.at n=8A057096
- Numbers k that can be expressed as k = w + x = y*z with w*x = y^3 + z^3 where w, x, y, and z are all positive integers.at n=22A057372
- Orders of finite perfect groups (groups such that G = G' where G' is the commutator subgroup of G).at n=35A060793
- Exponents in expansion of constant A065479 as a product zeta(n)^(-a(n)).at n=16A065491
- Numbers k such that k divides Sum_{i=1..k} gcd(k,i) = A018804(k).at n=41A066862
- Composite numbers k+1 such that k*phi(k+1) is a perfect square.at n=16A069068