5989
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 31
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6156
- Proper Divisor Sum (Aliquot Sum)
- 167
- 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
- 5824
- Möbius Function
- 1
- Radical
- 5989
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 49
- 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
- Numbers whose base-5 representation contains exactly two 2's and three 4's.at n=15A045288
- Numbers k such that 199*2^k-1 is prime.at n=36A050851
- Semiprimes p1*p2 such that p2>p1 and p2 mod p1 = 7.at n=31A064905
- Smallest argument m such that commutator[phi(m), gpf(m)] = 2n-1, where phi(m) = A000010(m) and gpf(m) = A006530(m), the largest prime factor of m.at n=49A070818
- Main diagonal of array in A083140.at n=15A083141
- Ordered hypotenuses of primitive Pythagorean triangles having legs that add up to a square.at n=10A088319
- Self-convolution of A107592.at n=6A107593
- Number of permutations of length n which avoid the patterns 213, 1234, 4312.at n=47A116720
- Array read by antidiagonals: T(d,k) (k >= 1, d = 1,2,3,4,5,6,...) = smallest semiprime s of k (not necessarily consecutive) semiprimes in arithmetic progression with common difference d, or 0 if there is no such arithmetic progression.at n=73A124570
- Expansion of 1/(x^k*(1-x-3*x^(k+1))) for k=7.at n=25A143458
- Numerators of triangle T(n,k), n>=1, 0<=k<=n - 1, read by rows: T(n,k) is the coefficient of x^k in polynomial p_n for the n-th row sequence of A145153.at n=38A145140
- Positive numbers y such that y^2 is of the form x^2+(x+809)^2 with integer x.at n=5A160203
- a(n) starts arithmetic progression of n terms separated by tau(a(n)), each term having the same number of divisors.at n=7A165497
- First term of maximal arithmetic progression with difference n, such that each term k has tau(k) = n.at n=3A165499
- Number of distinct solutions of sum{i=1..2}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 1..n-1.at n=36A180784
- Positive integers c in primitive (1/4)-Pythagorean triples (a,b,c) satisfying a<=b, in order of increasing a and then increasing b.at n=38A196264
- a(n) = (9*11^n - 1)/2.at n=3A199028
- Number of (w,x,y) with all terms in {0,...,n} and |w-x| + |x-y| + |y-w| >= w + x + y.at n=26A213489
- Triangular array read by rows: T(n,k) is the number of rooted identity trees with n nodes having exactly k subtrees from the root.at n=43A227774
- Number of rooted identity trees with n nodes and exactly 2 subtrees from the root.at n=12A227806