15139
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
- 2
- Divisor Sum
- 15140
- 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
- 15138
- Möbius Function
- -1
- Radical
- 15139
- 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
- 133
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1769
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 78 ones.at n=11A031846
- Fifth term of strong 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=34A054812
- Primes of the form 2*n^2+1.at n=15A090698
- Primes p such that p + googol is prime.at n=10A108250
- Primes and their indices such that when their respective SOD's are both prime, the SOD of the index is the nextprime of the prime SOD.at n=24A117458
- Larger of two consecutive primes whose sum is a square.at n=13A118591
- Larger member of twin prime pairs whose sum is a square.at n=7A118593
- The first 10 digits of the cube root of n contain the digits 0-9.at n=3A119517
- Twin prime pairs that sum to a power.at n=19A119768
- Triangle read by rows: T(n,k) is the number of deco polyominoes of height n and having k columns of odd length (0<=k<=n). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=46A121745
- Prime numbers p such that p^3 - p + 1 and p^3 + p - 1 are both primes.at n=22A137463
- Primes of the form k^2 + 10.at n=20A138355
- a(n) is n-th prime == 1 (mod 6n).at n=28A138906
- Primes congruent to 10 mod 41.at n=39A142207
- Primes congruent to 34 mod 53.at n=33A142564
- Primes congruent to 35 mod 59.at n=32A142762
- Primes congruent to 11 mod 61.at n=31A142809
- Form the difference table of the sequence {2^k*k!}, then divide k-th column entries by 2^k*k!. Array read by ascending antidiagonals, T(n, k) for n, k >= 0.at n=22A143410
- Smallest of 3 consecutive prime numbers such that p1*p2*p3*d1*d2=average of twin prime pairs; p1,p2,p3 consecutive prime numbers; d1(delta)=p2-p1, d2(delta)=p3-p2.at n=16A153409
- a(n) = 18*n^2 + 1.at n=28A157889