3970
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 7164
- Proper Divisor Sum (Aliquot Sum)
- 3194
- 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
- 1584
- Möbius Function
- -1
- Radical
- 3970
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 51
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = 20*a(n-1) - a(n-2).at n=3A001085
- Self-convolution of Fibonacci numbers.at n=15A001629
- a(n) = a(n-1) + a(n-6), with a(i) = 1 for i = 0..5.at n=36A005708
- Number of ways to quarter an n X n chessboard, with the central square removed for odd n.at n=8A006067
- Coordination sequence T5 for Zeolite Code MFS.at n=39A008177
- [ n(n-1)(n-2)(n-3)/11 ].at n=16A011921
- Expansion of 1/(1 - x^6 - x^7 - x^8 - ...).at n=42A017900
- a(n) = least m such that if r and s in {1/1, 1/3, 1/5, ..., 1/(2n-1)} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=34A024834
- Numerators of continued fraction convergents to sqrt(11).at n=5A041014
- Numerators of continued fraction convergents to sqrt(99).at n=5A041178
- Numerators of continued fraction convergents to sqrt(539).at n=7A042030
- Numerators of continued fraction convergents to sqrt(891).at n=7A042722
- a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 3.at n=13A049894
- Values of n^2 + 1 resulting from A050796.at n=34A050800
- a(n) = a(n-1) + a(n-2) + (n+2)*binomial(n+3, 3)/2, with a(0) = 1, a(1) = 7.at n=8A054469
- Number of primitive (period n) step cyclic shifted sequence structures using a maximum of five different symbols.at n=10A056442
- Let R(i,j) be the rectangle with antidiagonals 1; 2,3; 4,5,6; ...; the n-th Lucas number is in antidiagonal a(n).at n=33A057045
- Numbers k such that 3*2^k - 5 is prime.at n=28A057912
- Bisection of Fibonacci triangle A037027: odd-indexed members of column sequences of A037027 (not counting leading zeros).at n=29A060921
- Centered square numbers: a(n) = 4*n^2 + 4*n + 2.at n=31A069894