7057
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7058
- 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
- 7056
- Möbius Function
- -1
- Radical
- 7057
- 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
- 57
- 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
- 907
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p == 1 (mod 4) where class number of Q(sqrt p) increases.at n=6A002142
- Cuban primes: primes which are the difference of two consecutive cubes.at n=24A002407
- Primes of the form k^2 + 1.at n=16A002496
- For any circular arrangement of 0..n-1, let S = sum of squares of every sum of two contiguous numbers; then a(n) = # of distinct values of S.at n=34A007773
- Upper prime of a difference of 14 between consecutive primes.at n=35A031933
- Gaps of 7 in sequence A038593 (lower terms).at n=23A038653
- Numbers ending with '7' that are the difference of two positive cubes.at n=36A038862
- Numbers whose base-5 representation contains exactly three 1's and three 2's.at n=11A045232
- Primes with first digit 7.at n=24A045713
- a(n) = Sum_{i=0..floor(n/2)} T(2i,n-2i), array T as in A049723.at n=23A049726
- Primes p such that number of primes produced according to rules stipulated in Honaker's A048853 is 4.at n=23A050666
- Numbers n such that n^2 - 1 is expressible as the sum of two nonzero squares in exactly one way.at n=27A050797
- Primes such that the sum of the factorials of the digits is a perfect square.at n=22A052279
- Least prime in A031930 (lesser of 12-twins) whose distance to the next 12-twin is 2*n.at n=20A052355
- a(n) = 4*n^2 + 1.at n=42A053755
- Primes p with property that p concatenated with its emirp p' (prime reversal) forms a palindromic prime of the form 'primemirp' (rightmost digit of p and leftmost digit of p' are blended together - p and p' palindromic allowed).at n=36A054217
- Totient(n) and cototient(n) are squares.at n=32A054754
- Odd powers of primes of the form q = x^2 + 1 (A002496).at n=24A054755
- Numbers whose divisors have the form m^k + 1, k>1.at n=18A054964
- 5-morphic but not bimorphic, automorphic nor trimorphic.at n=37A056036