5848
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 11880
- Proper Divisor Sum (Aliquot Sum)
- 6032
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 2688
- Möbius Function
- 0
- Radical
- 1462
- Omega Function (Ω)
- 5
- 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
- 142
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t(n)=2*n+1 (odd numbers).at n=31A023865
- a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n-k+1), where k = floor(n/2), s = natural numbers, t = odd natural numbers.at n=30A024862
- Appending a digit to n^2 gives another perfect square.at n=16A031150
- Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 2,3,0.at n=4A037628
- Let (u1,u2) be successive untouchable numbers such that phi(u1) = phi(u2); sequence gives values of u1.at n=16A048189
- a(n) = Sum_{k=1..floor((n+1)/2)} T(n,2k-1), array T as in A049777.at n=31A049778
- Number of subdiagonal directed diagonally-convex animals with given diagonal semiperimeter.at n=8A053022
- Nonsquares which are the product of two numbers with the same digits (leading zeros are forbidden).at n=31A072443
- Least k for the Theodorus spiral to complete n revolutions.at n=23A072895
- Numbers k such that 10*k^2 + 9 is a square.at n=8A075836
- a(n) is the largest integer whose cube has n digits and first digit 1, except that a(2)=2.at n=11A083378
- Numerators of convergents to 3/(1 + sqrt(10)).at n=15A093611
- Unicode codes for the lunation runes, used in certain medieval Scandinavian perpetual calendar staves as golden numbers 1-19.at n=14A098476
- Triangle read by rows: T(n,k) is number of Dyck paths of semilength n having k ascents of length 1 that start at an odd level.at n=50A102405
- Positive integers n such that n^11 + 1 is semiprime.at n=30A105122
- Sum of primes q with prime(n) < q < 2*prime(n).at n=35A108313
- Numbers with composite sum of digits and prime sum of cubes of digits.at n=22A121642
- Numbers which are the product of a non-palindrome and its reversal, where leading zeros are not allowed.at n=31A129623
- a(n) = n*(n+1)*(8*n + 1)/6.at n=16A132124
- a(n) = prime(prime(prime(n) - 1) - 1) - 1, where prime(n) = n-th prime.at n=32A141208