6249
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8336
- Proper Divisor Sum (Aliquot Sum)
- 2087
- 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
- 4164
- Möbius Function
- 1
- Radical
- 6249
- 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
- 155
- 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
- Expansion of 1/(1 - x^4 - x^5 - x^6 - x^7).at n=40A017829
- Numbers k such that the continued fraction for sqrt(k) has period 82.at n=11A020421
- Least k>1 such that first n terms of Kolakoski sequence A000002 repeat in reverse order beginning at k-th term.at n=32A022295
- n written in fractional base 10/6.at n=49A024661
- 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=25A031550
- Trimorphic numbers: n^3 ends with n. Also m-morphic numbers for all m > 5 such that m-1 is not divisible by 10 and m == 3 (mod 4).at n=32A033819
- Smallest k for which k, 2k, ... nk all contain the digit 4.at n=8A039935
- Smallest k for which k, 2k, ... nk all contain the digit 4.at n=9A039935
- Trimorphic but not bimorphic nor automorphic.at n=24A056032
- Numbers k such that k^4 == 1 (mod 5^4).at n=39A056091
- Numbers k such that k^4 == 1 (mod 5^5).at n=7A056102
- a(n) = 2*n^n-1.at n=5A062207
- Numbers k such that the smoothly undulating palindromic number (75*10^k - 57)/99 is a prime.at n=8A062224
- Numbers k such that 2^(k+1) - k - 2 is prime.at n=10A063791
- a(1) = 4; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=37A074341
- a(n) = 2*5^n-1.at n=5A081655
- Number of compositions of n where the smallest part is greater than or equal to the number of parts.at n=39A098131
- Indices of primes in sequence defined by A(0) = 79, A(n) = 10*A(n-1) - 41 for n > 0.at n=8A101142
- Number of partitions of n into 3-smooth parts.at n=40A105420
- Diagonal sums of A107111, viewed as a number triangle.at n=12A107113