3930
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
- 16
- Divisor Sum
- 9504
- Proper Divisor Sum (Aliquot Sum)
- 5574
- 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
- 1040
- Möbius Function
- 1
- Radical
- 3930
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 144
- Smith Number
- yes
- 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 T7 for Zeolite Code NES.at n=40A008211
- Theta series of A_5 lattice.at n=25A008445
- n is equal to the number of 1's in all numbers <= n written in base 7.at n=1A014887
- a(n) = [ (3rd elementary symmetric function of S(n))/(first elementary symmetric function of S(n)) ], where S(n) = {first n+2 positive integers congruent to 2 mod 3}.at n=8A024399
- Sums of five consecutive squares: a(n) = n^2 + (n+1)^2 + (n+2)^2 + (n+3)^2 + (n+4)^2.at n=26A027578
- Every run of digits of n in base 4 has length 2.at n=34A033002
- Cycle of 2 steps possible for 'concatenate a(n) and nextprime(a(n)) is a prime'.at n=29A034592
- Numbers n such that string 3,0 occurs in the base 10 representation of n but not of n+1.at n=43A044743
- Numbers with exactly 4 distinct palindromic prime factors.at n=6A046402
- Row 3 of array in A047666.at n=17A047667
- Number of increasing arithmetic progressions in {1,2,3,...,n}, including trivial arithmetic progressions of lengths 1 and 2.at n=46A051336
- Number of reversible string structures with n beads using exactly four different colors.at n=8A056328
- Number of primitive (aperiodic) reversible string structures with n beads using exactly four different colors.at n=8A056338
- Numbers n > 13 such that x^n + x^13 + x^12 + x^11 + x^10 + x^9 + x^8 + x^7 + x^6 + x^5 + x^4 + x^3 + x^2 + x + 1 is irreducible over GF(2).at n=28A057489
- Squarefree numbers sandwiched between a pair of twin primes.at n=31A070195
- Group the positive integers as (1, 2), (3, 4, 5), (6, 7, 8, 9, 10), (11, 12, 13, 14, 15, 16, 17), ... the n-th group containing prime(n) elements. Except the first, all groups contain an odd number of elements and hence have a middle term. Sequence gives the middle terms starting from group 2.at n=43A073612
- a(n) is the coefficient of x^n in x/(1 + Sum_{k>=1} (1/2)*(prime(k+1) - 1)*x^k).at n=45A074142
- Sum of terms of n-th group in A075383.at n=14A075386
- Sum of the quadratic residues of prime(n).at n=31A076409
- Expansion of (1-x)^(-1)/(1-x+2*x^2+2*x^3).at n=17A077878