5671
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 5832
- Proper Divisor Sum (Aliquot Sum)
- 161
- 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
- 5512
- Möbius Function
- 1
- Radical
- 5671
- 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
- yes
- 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
- 80
- 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
- Number of series-reduced trees with n nodes.at n=21A000014
- A sixth-order linear divisibility sequence: a(n+6) = -3*a(n+5) - 5*a(n+4) - 5*a(n+3) - 5*a(n+2) - 3*a(n+1) - a(n).at n=27A005120
- a(n) = p*(p-1)/2 for p = prime(n).at n=27A008837
- Numbers k such that the continued fraction for sqrt(k) has period 72.at n=15A020411
- Numbers whose sum of divisors is a cube.at n=30A020477
- Exactly 5 digits from {1,2,3,4,5,6,7,8,9} can precede a(n) to form a lucky number.at n=25A032701
- a(n) = (2*n-1)*(4*n-1).at n=27A033567
- Cycle of 2 steps possible for 'concatenate a(n) and nextprime(a(n)) is a prime'.at n=38A034592
- Lexicographically earliest sequence of pairwise coprime triangular numbers.at n=9A034792
- Numbers k such that 75*2^k-1 is prime.at n=36A050563
- Birthday set of order 9: i.e., numbers congruent to +- 1 modulo 2, 3, 4, 5, 6, 7, 8 and 9.at n=36A057541
- Centered 9-gonal (also known as nonagonal or enneagonal) numbers. Every third triangular number, starting with a(1)=1.at n=35A060544
- Triangular numbers with product of digits also a triangular number.at n=46A061380
- Triangular numbers which are the product of two primes.at n=13A068443
- Triangular numbers such that the product of digits is also a (positive) triangular number.at n=11A069077
- Centered 15-gonal numbers: a(n) = (15*n^2 - 15*n + 2)/2.at n=27A069128
- Permutation of natural numbers induced by reranking plane binary trees given in the standard lexicographic order (A014486) with an "arithmetic global ranking algorithm", using A072734 as the packing bijection N X N -> N.at n=67A072787
- Binomial coefficients C(p, k), 2<=k<=p-2, sorted, with duplicates removed, p being prime.at n=40A082581
- Triangular numbers which are one more than a product of distinct triangular numbers.at n=7A083517
- Gregorian calendar years with Ascension Day in April.at n=17A084427