7477
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
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7478
- 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
- 7476
- Möbius Function
- -1
- Radical
- 7477
- 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
- 88
- 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
- 946
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Where the prime race among 5k+1, ..., 5k+4 changes leader.at n=44A007353
- a(n) = prime(n*(n+1)/2).at n=42A011756
- Numbers k such that the continued fraction for sqrt(k) has period 85.at n=7A020424
- Primes that contain digits 4 and 7 only.at n=3A020465
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t = A002808 (composite numbers).at n=37A023863
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = (composite numbers).at n=36A024860
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 19.at n=2A031607
- Upper prime of a difference of 18 between consecutive primes.at n=31A031937
- Primes that are concatenations of n with n + 3.at n=9A032626
- Numbers having three 7's in base 10.at n=11A043519
- Upper members of a "good pair" of the form (k, 2*k +- 1).at n=41A046862
- Prime number spiral (clockwise, West spoke).at n=15A054570
- Number of dissimilar ternary squarefree words of length n+1.at n=29A060688
- Primes starting and ending with 7.at n=17A062334
- Primes of form Sum_{k=1..n} (prime(k)+1).at n=25A062736
- Initial terms of groups in A075639.at n=43A075641
- Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <=6 (i.e., when d=2,4 or 6) and forming d-pattern=[4, 6, 2]; short d-string notation of pattern = [462].at n=17A078851
- Primes having only {1, 4, 7} as digits.at n=20A079651
- First row of square array A082011.at n=43A082012
- a(n) = 4*n^2 + 10*n + 1.at n=42A082112