13615
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18720
- Proper Divisor Sum (Aliquot Sum)
- 5105
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9312
- Möbius Function
- -1
- Radical
- 13615
- 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
- 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
- 89
- 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
- Numbers that, when expressed in base 7 and then interpreted in base 10, yield a multiple of the original number.at n=31A032549
- Numbers k such that 2^k + 9 is prime.at n=43A057196
- Numbers k that, when expressed in base 7 and then interpreted in base 10, give a multiple of k.at n=32A062944
- Numbers n such that sum of squares of even digits of n equals sum of squares of odd digits of n.at n=15A076164
- If M(n) is the n-th Mersenne prime, then a(n) is the smallest positive integer such that 2*a(n)*M(n)*M(n+1)*M(n+2)-1 is prime.at n=18A093192
- Triangle, read by rows, equal to the matrix cube of A113370.at n=17A113378
- Numbers k such that k divides 1 + Sum_{j=1..k} prime(j)^19.at n=19A233768
- Numbers that are the concatenation of three (not necessarily distinct) primes whose sum is prime, and are also the product of three (not necessarily distinct) primes whose sum is prime.at n=31A385452