6321
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 10032
- Proper Divisor Sum (Aliquot Sum)
- 3711
- 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
- 3528
- Möbius Function
- 0
- Radical
- 903
- Omega Function (Ω)
- 4
- 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
- 155
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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 k such that x^k + x + 1 is irreducible over GF(2).at n=26A002475
- Divisors of 2^42 - 1.at n=28A003547
- a(n) = Sum_{k=1..n-1} lcm(k,n-k).at n=42A006580
- Numbers k that divide s(k), where s(1)=1, s(j)=9*s(j-1)+j.at n=29A014857
- Numbers k that divide s(k), where s(1)=1, s(j)=15*s(j-1)+j.at n=33A014865
- Numbers k such that k divides 4^k - 1.at n=34A014945
- Odd numbers k that divide 25^k - 1.at n=46A014962
- Numbers k such that k | 5^k + 1.at n=33A015951
- Ordered sequence of distinct terms of the form floor(x^i * floor(x^j)), i,j >= 0, where x = sqrt(7).at n=27A022771
- 7 times triangular numbers: 7*n*(n+1)/2.at n=42A024966
- Number of partitions of n into an even number of parts, the least being 3; also, a(n+3) = number of partitions of n into an odd number of parts, each >=3.at n=55A027195
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 52.at n=29A031550
- Row sums of triangle A049375.at n=3A039746
- Numbers k that divide 10^k + 2^k.at n=47A045583
- Numbers k that divide 5^k + 4^k.at n=24A045590
- Numbers k that divide 10^k + 8^k.at n=41A045608
- Smallest order m > 0 for which there are n nonisomorphic finite groups of order m, or 0 if no such order exists.at n=21A046057
- a(n) = 4*n^2 - 10*n + 7.at n=40A054554
- Numbers k such that k | 6^k + 5^k + 4^k + 3^k + 2^k + 1^k.at n=36A056745
- n is odd and sum of digits of n equals the numbers of divisors of n.at n=32A057532