3965
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 5208
- Proper Divisor Sum (Aliquot Sum)
- 1243
- 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
- 2880
- Möbius Function
- -1
- Radical
- 3965
- 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
- 100
- 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) = (6*n+1)*(6*n+5).at n=10A001513
- a(n) = (4*n+1)*(4*n+5).at n=15A003185
- a(n) = a(n-4) + a(n-5), with a(0)=1, a(1)=a(2)=a(3)=0, a(4)=1.at n=63A017827
- Generalized Catalan Numbers x^4*A(x)^2 -(1-x+x^4+x^5+x^6+x^7)*A(x) + 1 =0.at n=23A023430
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (Lucas numbers), t = (composite numbers).at n=17A024471
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (Lucas numbers), t = (composite numbers).at n=16A025091
- [ Sum{(sqrt(j+1)-sqrt(i+1))^3} ], 1 <= i < j <= n.at n=30A025223
- Numbers that are the sum of 2 nonzero squares in exactly 4 ways.at n=14A025287
- Numbers that are the sum of 2 nonzero squares in 4 or more ways.at n=14A025295
- Numbers that are the sum of 2 distinct nonzero squares in exactly 4 ways.at n=14A025305
- Numbers that are the sum of 2 distinct nonzero squares in 4 or more ways.at n=14A025314
- Quasi-Carmichael numbers to base -3: squarefree composites n such that for every prime p that divides n, p+3 divides n+3.at n=4A029563
- Numbers whose square contains no loops in its digits (assumes 1, 2, 3, 5, 7 have no loops and 0, 4, 6, 8, 9 do).at n=44A034905
- Numbers whose base-4 representation contains exactly two 1's and four 3's.at n=11A045123
- Numbers whose base-5 representation contains exactly three 1's and two 3's.at n=23A045246
- Discriminants of real quadratic fields of ERD-type with class groups of exponent 2 and discriminants of the form D = r^2*k^2+4k, k odd.at n=39A051992
- Column 2 of triangle A055300.at n=12A055301
- Another variant of Boustrophedon transform applied to 1, 0, 0, 0, ...at n=6A059032
- Triangle in A059032 read by rows from left to right.at n=21A059033
- Triangle in A059032 read by rows in natural order.at n=27A059034