15049
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
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 15300
- Proper Divisor Sum (Aliquot Sum)
- 251
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14800
- Möbius Function
- 1
- Radical
- 15049
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- yes
- 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 k such that the continued fraction for sqrt(k) has period 89.at n=17A020428
- 4-white numbers: partition digits of n^4 into blocks of 4 starting at right; sum of these 4-digit numbers equals n.at n=6A037044
- Combined Diophantine Chebyshev sequences A054488 and A077413.at n=11A077241
- Bisection (odd part) of Chebyshev sequence with Diophantine property.at n=5A077413
- Numbers n such that n and its reversal are distinct brilliant numbers (A078972).at n=19A097435
- Counterexamples to the conjecture that an even, prime-indexed triangular plus 1 equals a prime or that an odd, prime-indexed triangular minus 2 equals a prime.at n=13A097785
- Triangular Kaprekar-like numbers: numbers k such that the base-10 representation of T(k) = k*(k+1)/2 is the concatenation of two numbers x and y such that x + y = k.at n=33A110939
- Both n and the reverse of n are brilliant numbers (A078972).at n=31A115655
- Expansion of 1/(1 - x + x^3 - 3*x^4 + x^5 - x^7 + x^8).at n=32A147593
- The first number that is (at least) n-fold intrinsically 3-palindromic (represented in base ten).at n=7A171702
- Partial sums of Sum_{k=1..n} n/gcd(n,k), or partial sums of Sum_{d|n} d*phi(d) (see A057660).at n=38A174405
- Parameters n for which the elliptic curve y^2=x^3-n has rank 4.at n=18A179137
- Number of cubic plane graphs with 2n nodes, minimal face size 4 and maximal face size 6.at n=25A219748
- Least number k such that n divides gcd(sigma(k), phi(k)) (A009223).at n=24A222713
- Least number k such that n divides gcd(sigma(k), phi(k)) (A009223).at n=49A222713
- Beastly reciprocals, or numbers k such that digitsum(1/k) = 666.at n=31A244661
- a(n) = (n+1)^3 - n^2.at n=24A261893
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 131", based on the 5-celled von Neumann neighborhood.at n=28A270223
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 595", based on the 5-celled von Neumann neighborhood.at n=24A273142
- Numbers k such that 88*10^k + 7 is prime.at n=22A274914