6461
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 8064
- Proper Divisor Sum (Aliquot Sum)
- 1603
- 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
- 5040
- Möbius Function
- -1
- Radical
- 6461
- 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
- 75
- 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
- Number of discordant permutations.at n=10A000561
- Generalized Stirling numbers, [n+2,n]_2.at n=13A001701
- Expansion of 1/((1-2x)(1-5x)(1-6x)).at n=4A016295
- Pseudoprimes to base 57.at n=37A020185
- Numbers n such that prime(n) == -1 (mod n).at n=11A045924
- Odd composite numbers divisible by the sum of their prime factors (counted with multiplicity).at n=22A046347
- Duplicate of A045924.at n=11A049204
- a(n)=T(n,n+2), array T as in A049735.at n=31A049742
- a(0)=4, a(1)=0, a(2)=0, a(3)=3; thereafter a(n) = a(n-3) + a(n-4).at n=44A050443
- Numbers k such that phi(k)*d(k) is a multiple of sigma(k), where d(k) is the number of divisors of k.at n=28A050934
- a(n) = a(n-1) + the number of primes <= a(n-1).at n=37A061535
- Length of period of continued fraction expansion of square root of 3^n-1.at n=18A062345
- Primitive subsequence of A066031: terms of A066031 which are not a multiple of some previous terms.at n=44A064623
- a(n) is the least index such that the least primitive root of the a(n)-th prime is n, or zero if no such prime exists.at n=34A066529
- Numbers k that divide prime(k)+1 or prime(k)-1.at n=18A078931
- Number of partitions of n into numbers having in binary representation at most trailing zeros.at n=37A087750
- a(n) = a(n-1) + a([n/2]) + 1, a(1) = 1.at n=44A102378
- Numbers k such that prime(k+1) == 3 (mod k).at n=8A105288
- The i-th term of the generalized Fibonacci sequence [0,k,k,2k,3k,...] is given by the formula F(i) = round( k/sqrt(5) * phi^i ) provided i >= s(k); a(n) = smallest value of k such that s(k) = n.at n=17A111917
- Let T(S,Q) be the sequence obtaining by starting with S and repeatedly reversing the digits and adding Q to get the next term. This is T(1016,5), the first S for which T(S,5) reaches a cycle of length 36.at n=18A118879