7481
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7482
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7480
- Möbius Function
- -1
- Radical
- 7481
- 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
- 163
- 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
- 947
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/4.at n=44A001134
- Primes of the form k^2 - k - 1.at n=43A002327
- a(n) = floor(3^n / 2^n).at n=22A002379
- [ sqrt(3/2)^n ].at n=44A014215
- Numbers k such that the continued fraction for sqrt(k) has period 15.at n=35A020354
- n written in fractional base 10/7.at n=41A024662
- Number of distinct products i*j with 0 <= i, j <= n-th prime.at n=37A027419
- Primes that are palindromic in base 6.at n=28A029974
- Primes that are concatenations of n with n + 7.at n=10A032630
- Denominators of continued fraction convergents to sqrt(521).at n=10A041997
- p, p+6 and p+8 are all primes (A046138) but p+2 is not.at n=39A049438
- Primes p from A031924 such that A052180(primepi(p)) = 7.at n=38A052231
- Primes p whose reciprocal has period (p-1)/10.at n=11A056215
- Primes p such that x^24 = 2 has no solution mod p, but x^12 = 2 has a solution mod p.at n=35A059331
- Primes associated with A066042.at n=23A066146
- Primes of the form floor((3/2)^k).at n=7A067904
- (p^2-5)/4 for odd primes p.at n=38A074367
- Smallest number whose cube begins and ends in n, or 0 if no such number exists.at n=41A077752
- a(n) = prime(n*(n+1)/2 + 1).at n=43A078721
- Numbers n such that A003313(n) = A003313(2n).at n=26A086878