13041
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 20
- Divisor Sum
- 23232
- Proper Divisor Sum (Aliquot Sum)
- 10191
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7128
- Möbius Function
- 0
- Radical
- 483
- Omega Function (Ω)
- 6
- 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
- yes
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- yes
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 45
- 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
- a(n) = n^2*(2*n^2 - 1); also Sum_{k=0..n-1} (2k+1)^3.at n=9A002593
- a(n) = 2*3^(2*n)-3^n.at n=4A010035
- a(n) = (2*n+1)*(4*n+1).at n=40A014634
- Expansion of 1/((1-2x)(1-4x)(1-5x)(1-6x)).at n=4A025958
- Number of partitions satisfying cn(2,5) < cn(0,5) + cn(1,5) + cn(4,5) and cn(3,5) < cn(0,5) + cn(1,5) + cn(4,5).at n=35A039873
- Numerators of continued fraction convergents to sqrt(683).at n=6A042312
- Numerators of continued fraction convergents to sqrt(723).at n=5A042392
- T(n,n+1), array T as in A047120.at n=8A047126
- Numbers n such that n | 10^n + 9^n + 8^n + 7^n + 6^n + 5^n + 4^n + 3^n + 2^n.at n=35A057287
- Smallest triangular numbers that contain the digits of n anywhere in their middle.at n=30A062829
- Triangular numbers of the form 21*k.at n=30A069499
- Triangular numbers with property that swapping first and last digits also gives a triangular number.at n=34A069708
- Triangular numbers which are 6-almost primes.at n=10A076580
- Smallest triangular number > 1 and == 1 (mod prime(n)).at n=37A087397
- Triangular numbers with palindromic indices.at n=25A089717
- Numbers n such that there are integers a < b with a^2+(a+1)^2+...+(n-1)^2 = (n+1)^2+(n+2)^2+...+b^2.at n=7A094552
- Transform of n^3 by the Riordan array (1/(1-x^2), x).at n=17A105636
- Hexagonal numbers for which the product of the digits is also a hexagonal number.at n=33A117063
- Triangular numbers for which the sum of the digits is a square.at n=17A117404
- Triangular numbers for which the sum of the digits equals the sum of the digits of the next triangular number.at n=8A117511