13764
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 34048
- Proper Divisor Sum (Aliquot Sum)
- 20284
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4320
- Möbius Function
- 0
- Radical
- 6882
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- 107
- Smith Number
- yes
- 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
- yes
- Odd
- no
Appears in sequences
- Perimeters of more than one primitive Pythagorean triangle.at n=21A024408
- 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 78.at n=29A031576
- XOR-convolution of squares A000290 with themselves.at n=27A033460
- Smaller of Smith brothers.at n=9A050219
- Numbers k such that the k-th prime is of the form 2*j^2 + 1.at n=38A090612
- Largest member of the n-th row of the triangular triangle (A093445).at n=40A093446
- a(n) = 2*n*(7*n + 5).at n=31A195027
- Numbers k such that k and k+1 have the same binary XOR of divisors.at n=29A227443
- Number of partitions p of n such that median(p) >= multiplicity(min(p)).at n=39A240216
- Numbers that are the sum of nine fourth powers in nine or more ways.at n=35A345593
- Numbers that are the sum of nine fourth powers in ten or more ways.at n=7A345594
- Numbers that are the sum of nine fourth powers in exactly ten ways.at n=7A345852
- Positions of -2's in A346242.at n=49A354822
- a(1)=1; for n>1, a(n) = a(n-1) / k if there exists an unused positive integer k (choose the smallest) such that a(n) is a distinct positive integer; otherwise a(n) = a(n-1) * k if the same conditions apply.at n=42A371359