7455
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 13824
- Proper Divisor Sum (Aliquot Sum)
- 6369
- 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
- 3360
- Möbius Function
- 1
- Radical
- 7455
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 70
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- Number of strict 3rd-order maximal independent sets in cycle graph.at n=41A007392
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 5.at n=37A013593
- Numbers k that divide s(k), where s(1)=1, s(j)=15*s(j-1)+j.at n=37A014865
- Numbers whose sum of divisors is a cube.at n=39A020477
- Number of 1's in n-th term of A022470.at n=33A022472
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (F(2), F(3), ...), t = A001950 (upper Wythoff sequence).at n=19A024594
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (F(2), F(3), F(4), ...), t = A001950 (upper Wythoff sequence).at n=18A025108
- Triangle T(n,k) of series-reduced (or homeomorphically irreducible) labeled graphs with n nodes and k edges, k=0..binomial(n,2).at n=50A060514
- 2-nadirs of phi: numbers k such that phi(k-2) > phi(k-1) > phi(k) < phi(k+1) < phi(k+2).at n=38A076773
- Greedy frac multiples of 1/Pi: a(1)=1, Sum_{n>0} frac(a(n)*x) = 1 at x=1/Pi, where "frac(y)" denotes the fractional part of y.at n=27A080142
- Arrange n^2 octagons that each have area 7 so that they leave (n-1)^2 square gaps each with area 2; a(n) is the total area of these polygons.at n=28A086640
- a(n) = floor(11^n/8^n).at n=28A094995
- t(n)_n where t() = triangular numbers A000217.at n=34A122634
- Numbers k for which nontrivial positive magic squares of exactly 8 different orders with magic sum k exist. For a definition of nontrivial positive magic squares, see A125005.at n=34A125015
- Numbers k such that k^2 divides 16^k-1.at n=43A128396
- Numbers n where |sinc(n)| decreases monotonically to 0 (where sinc(x)=sin(x)/x).at n=46A131975
- Sum of the lengths of the longest increasing subsequence over all 321-avoiding permutations of [n].at n=7A132889
- Number of walks from origin to (1,0,0) in a cubic lattice.at n=3A135390
- Numbers k such that k and k^2 use only the digits 0, 2, 4, 5 and 7.at n=33A136899
- Triangle read by rows: T(n,k) = number of partitions of [1..k] into n nonempty clumps of sizes 1, 2, 3, 4 or 5 (n >= 0, 0 <= k <= 5n).at n=28A151338