6501
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
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 9504
- Proper Divisor Sum (Aliquot Sum)
- 3003
- 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
- 3920
- Möbius Function
- -1
- Radical
- 6501
- 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
- yes
- 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
- 137
- 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
- Expansion of 1/((1-x)^3*(1-x^3)^2).at n=30A011779
- a(n) = floor(n*(n-1)*(n-2)/30).at n=59A011912
- Odd pentagonal numbers.at n=33A014632
- Number of 5-tuples of different integers from [ 1,n ] with no common factors among triples.at n=19A015646
- Powers of cube root of 2 rounded down.at n=38A017979
- Powers of cube root of 4 rounded down.at n=19A017985
- Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite AFG = Afghanite (Na2,Ca,K2)12[Al24Si24O96] starting with a T3 atom.at n=5A018954
- Pseudoprimes to base 14.at n=22A020142
- Expansion of 1/((1-x)^4*(1-x^2)^2).at n=16A028346
- Base-4 digits are, in order, the first n terms of the periodic sequence with initial period 1,2,1.at n=6A037537
- Numbers whose base-5 representation contains exactly three 0's and two 2's.at n=35A045186
- Pentagonal numbers with even index.at n=33A049452
- Numbers k such that sum of factorials of digits of k equals pi(k) (A000720).at n=1A049529
- Number of partitions of n such that all parts are neither relatively prime (cf. A000837) nor are they periodic with each part occurring the same number of times (cf. A024994).at n=61A060034
- Centered 20-gonal (or icosagonal) numbers.at n=25A069133
- Positive numbers k such that the number of primes between k and 2*k is different from the number of primes between m and 2*m for every number m != k.at n=40A084142
- a(n) = floor((Pi/sqrt(2))^n).at n=11A095214
- Greater of number pair whose squares are reversals of each other, with no leading zeros allowed.at n=26A106324
- The smallest part summed over all partitions of n in which every integer from the smallest part to the largest part occurs.at n=51A117467
- Pentagonal numbers for which the sum of the digits is also a pentagonal number.at n=8A117709