15427
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
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 15428
- 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
- 15426
- Möbius Function
- -1
- Radical
- 15427
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 84
- 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
- 1802
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Sum of 12 nonzero 8th powers.at n=34A003390
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 70 ones.at n=26A031838
- Numbers k such that 221*2^k+1 is prime.at n=33A032487
- Fifth term of weak prime quintets: p(m-3)-p(m-4) < p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1).at n=40A054827
- Sixth term of weak prime sextet: p(m-4)-p(m-5) < p(m-3)-p(m-4) < p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1).at n=5A054833
- Seventh term of weak prime septet: p(m-5)-p(m-6) < p(m-4)-p(m-5) < p(m-3)-p(m-4) < p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1).at n=0A054840
- Least initial value for an Euclid/Mullin sequence whose 4th term is prime(n). prime(1)=2 is never a fourth term, so offset=2.at n=34A094465
- Triangle read by rows in which the n-th row contains the least set of n successive primes whose successive difference forms an arithmetic progression with common difference 2, (successive even numbers).at n=27A094749
- Prime numbers which when written in base 7 have a composite digit-sum.at n=21A096790
- Greatest prime factor of prime(n)! / prime(n)# + 1.at n=6A103892
- a(n) = a(n-1) + 2*n^2 with a(1) = 1.at n=27A112524
- Primes of the form 2*3*5*7*k + 97.at n=37A141899
- Primes congruent to 11 mod 47.at n=36A142362
- Primes congruent to 4 mod 53.at n=34A142534
- Primes congruent to 28 mod 59.at n=28A142755
- Primes congruent to 55 mod 61.at n=31A142853
- Expansion of g.f.: exp( Sum_{n>=1} sigma(5*n)*x^n/n ).at n=8A182821
- Primes p such that f(f(p)) is prime, where f(x) = x^4-x^3-x^2-x-1.at n=30A230029
- Primes p with q(p) - 1 also prime, where q(.) is the strict partition function (A000009).at n=51A234644
- Primes p such that p+12, p+1234 and p+123456 are also prime.at n=7A236304