6423
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8568
- Proper Divisor Sum (Aliquot Sum)
- 2145
- 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
- 4280
- Möbius Function
- 1
- Radical
- 6423
- 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
- 124
- 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
- One-half the number of permutations of length n with exactly 2 rising or falling successions.at n=8A000349
- Triangle read by rows: T(n,k) is one-half the number of permutations of length n with exactly n-k rising or falling successions, for n >= 1, 1 <= k <= n. T(1,1) = 1 by convention.at n=33A010028
- n written in fractional base 8/6.at n=27A024648
- Number of distinct products ijk with 0 <= i < j < k <= n.at n=49A027429
- 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 25.at n=32A031523
- a(n) = 1 + Sum_{i=1..n} phi(i)^2.at n=36A049454
- Numbers n such that 151*2^n-1 is prime.at n=4A050617
- Moebius transform of A001405 (binomial(n, floor(n/2))).at n=14A062791
- Triangle read by rows: T(n,k) = one-half number of permutations of length n with exactly k rising or falling successions, for n >= 1, 0 <= k <= n-1. T(1,0) = 1 by convention.at n=30A086856
- Column 4 of an array closely related to A083480. (Both arrays have shape sequence A083479).at n=8A089574
- Number of digits in A110776(n).at n=14A110777
- n+sigma(n)+sigma(sigma(n)) is a triangular number.at n=30A116015
- Number of "fragments" with n nodes generated from the simple cubic lattice.at n=7A122675
- a(n) = 338*n + 1.at n=18A158000
- a(n) = 169n + 1.at n=37A158221
- a(n) = 38*n^2 + 1.at n=13A158593
- Array T(n,m) = A177944(2*n,2*m) read by antidiagonals.at n=23A177970
- Array T(n,m) = A177944(2*n,2*m) read by antidiagonals.at n=25A177970
- Number of permutations of 1..n with displacements restricted to {-4,-2,0,1,3}.at n=12A189583
- Number of solutions to the Diophantine equation x1*x2 + x2*x3 + x3*x4 + x4*x5 + x5*x6 = n, with all xi >= 1.at n=45A191832