13498
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 21492
- Proper Divisor Sum (Aliquot Sum)
- 7994
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6336
- Möbius Function
- -1
- Radical
- 13498
- 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
- 45
- 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
- Numbers k such that the continued fraction for sqrt(k) has period 41.at n=26A020380
- Numbers of the form p^3 + q^3, p, q primes.at n=39A086119
- a(n) is the least k such that (k*prime(n)#)^2 + 1, ((k+1)*prime(n)#)^2 + 1 and ((k+2)*prime(n)#)^2 + 1 are 3 primes, where prime(n)# is the n-th primorial.at n=38A098765
- Numbers which are the sum of two positive cubes and divisible by 17.at n=14A099178
- Sums of two distinct prime cubes.at n=32A120398
- Sums of 2 cubes of distinct odd primes.at n=24A137632
- a(n) = a(n-1)+a(n-2)-Floor(a(n-3)/2)-Floor(a(n-8)/2); initial terms are 0, 1, 1, 2, 3, 5, 7, 11.at n=27A173199
- Right edge of the triangle in A033291.at n=33A192736
- a(n) = 3*a(n-1) + 5*a(n-2), with a(0)=1, a(1)=2.at n=7A197189
- Number of (weakly) unimodal compositions of n where all parts 1, 2, ..., m appear where m is the largest part.at n=27A227038
- Number of times an evil number is encountered when iterating from 2^(n+1)-2 to (2^n)-2 with the map x -> x - (number of runs in binary representation of x).at n=18A255063
- 26-gonal numbers: a(n) = n*(12*n-11).at n=34A255185
- Expansion of psi(-x^3) / f(-x) in powers of x where psi(), f() are Ramanujan theta functions.at n=42A271593
- Numbers that are, at the same time, the sum of: two positive squares, a positive square and a positive cube, and two positive cubes. In other words, intersection of A000404, A003325 and A055394.at n=28A273498
- Numbers k such that phi(6k) is either phi(6k-2) or phi(6k+2), where phi is Euler's totient function A000010.at n=16A279011
- Numbers k such that phi(6k) = phi(6k+2), where phi is Euler's totient function A000010.at n=4A279184
- Even numbers that are the sum of two odd prime cubes.at n=30A286836
- a(n) = PrimePi(n^3) - PrimePi(n)^3, where PrimePi = A000720.at n=58A291538
- Numbers k such that (58*10^k + 329)/9 is prime.at n=20A294570
- Number of length-n binary strings where every prefix is either a palindrome, or the concatenation of two palindromes.at n=48A297702