13366
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 20664
- Proper Divisor Sum (Aliquot Sum)
- 7298
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6480
- Möbius Function
- -1
- Radical
- 13366
- 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
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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
- yes
- Odd
- no
Appears in sequences
- Generalized Fibonacci numbers A_{n,3}.at n=33A006208
- a(n) = 2*n*(4*n - 1).at n=41A014635
- Pseudoprimes to base 51.at n=40A020179
- Triangular numbers (A000217) with prime indices.at n=37A034953
- Even triangular numbers with prime indices.at n=19A034955
- Triangular numbers with every digit a triangular number.at n=14A062100
- Smallest triangular numbers that contain the digits of n anywhere in their middle.at n=33A062829
- Triangular numbers which are a concatenation of two or more positive triangular numbers.at n=25A068144
- Triangular number x such that x + reverse of x is a prime.at n=6A072387
- Triangular numbers which are also happy numbers (cf. A007770).at n=24A076712
- a(n) = (25*n^2 - 15*n + 2)/2.at n=33A080857
- Numbers n with digits in nondecreasing order such that sum of the reciprocal of digits is an integer.at n=27A091784
- Triangular numbers whose sum of squared digits is also triangular.at n=12A094890
- Numbers of the form prime(n) + prime(n+1) - 2 that are also triangular numbers, T(k) = k(k+1)/2.at n=17A110891
- Triangular numbers whose digit reversal is a brilliant number (A078972).at n=5A115678
- Triangular numbers for which the sum of the digits is a prime number.at n=34A117512
- Triangular numbers composed of digits {1,3,6}.at n=7A119115
- Triangular numbers that are products of three distinct primes.at n=39A128896
- Triangular numbers T such that T+1 is a prime.at n=41A129545
- Hexagonal numbers (A000384) which are sum of 2 other hexagonal numbers > 0.at n=13A133215