13487
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 13488
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 13486
- Möbius Function
- -1
- Radical
- 13487
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 138
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1599
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Smallest prime p such that the product of q/(q-1) over the primes from prime(n) to p is greater than 2.at n=27A001275
- a(n) = floor(n*phi^14), where phi is the golden ratio, A001622.at n=16A004929
- Third term of weak prime quintets: p(m-1)-p(m-2) < p(m)-p(m-1) < p(m+1)-p(m) < p(m+2)-p(m+1).at n=29A054825
- Fourth term of weak prime quintets: p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1) < p(m+1)-p(m).at n=28A054826
- Fourth term of weak prime sextet: p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1) < p(m+1)-p(m) < p(m+2)-p(m+1).at n=1A054831
- McKay-Thompson series of class 9B for the Monster group.at n=36A058091
- Consider the family of multigraphs enriched by the species of odd sets. Sequence gives number of those multigraphs with n labeled edges.at n=6A098636
- a(1)=2, a(2)=3; a(n)=a(n-2)+s^2, where s^2 is a minimal square such that a(n) is prime and is not already in the sequence.at n=43A127494
- Prime numbers k such that k^2 +- (k+1) are primes.at n=35A137460
- Primes of the form 210k + 47.at n=33A140850
- Primes congruent to 45 mod 47.at n=37A142396
- Primes congruent to 12 mod 49.at n=33A142424
- Primes congruent to 25 mod 53.at n=32A142555
- Primes congruent to 12 mod 55.at n=40A142609
- Primes congruent to 35 mod 59.at n=27A142762
- Primes congruent to 6 mod 61.at n=27A142804
- Primes of the form : (p-n)/(n+1)=prime and (n+1)*p+n=prime. n=3.at n=41A152293
- Middle of 3 consecutive prime numbers, p1, p2, p3, such that p1*p2*p3*d1*d2 = average of twin prime pairs; d1 (delta) = p2 - p1, d2 (delta) = p3 - p2.at n=15A153410
- Primes P(n) such that 2*P(n) - P(n+1) has all factors less than P(n+1) - P(n). This means that no prime less than P(n) can divide P(n) to give a remainder added to P(n) to give P(n+1).at n=37A155128
- Primes p such that q = p^2 + p + 1 is an emirp.at n=22A178545