7490
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
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 15552
- Proper Divisor Sum (Aliquot Sum)
- 8062
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2544
- Möbius Function
- 1
- Radical
- 7490
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 163
- 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
- yes
- Odd
- no
Appears in sequences
- Coordination sequence for 5-dimensional lonsdaleite.at n=10A008525
- a(0) = 1, a(n) = 13*n^2 + 2 for n>0.at n=24A010004
- a(n) = (d(n)-r(n))/2, where d = A026063 and r is the periodic sequence with fundamental period (1,1,0,1).at n=34A026064
- Self-convolution of row n of array T given by A026758.at n=7A027231
- Triangle read by rows: matrix 5th power of the Stirling-1 triangle A008275.at n=33A039817
- Number of basis partitions of n+36 with Durfee square size 6.at n=24A053801
- Non-balanced numbers in A015771.at n=12A078549
- Numbers n not of the form i^2+(i+1)^2 such that there are integers a < b with a^2+(a+1)^2+...+(n-1)^2 = n^2+(n+1)^2+...+b^2.at n=17A094523
- n*(n-1)*(n^2-n+4)/6.at n=15A103290
- Starts with 2; has two properties: concatenation of its digits is same string as concatenation of digits of its first differences and sequence and first differences have no term in common. When there is a choice in choosing the next term in the first differences, choose the smallest number not yet present in either the sequence or its first differences.at n=38A139334
- a(n) = 250*n - 10.at n=29A154378
- a(n) = n*(n+1)*(5*n+7)/6.at n=20A162148
- Number of triples (a, b, c) with gcd(a, b, c) = 1 and -n <= a,b,c <= n.at n=10A175549
- Numbers m such that all three values m^2 + 13^k, k = 1, 2, 3, are prime.at n=31A178639
- a(n) = n*(6*n+4).at n=35A202804
- Coefficient array for the fourth power of Chebyshev's S-polynomials as a function of x^2.at n=42A219234
- a(n) = n*p(n)-spt(n) (= n*A000041(n) - A092269(n)).at n=18A220907
- Number of nX3 0..1 arrays with successive rows and columns fitting to straight lines with nondecreasing slope, with a single point array taken as having zero slope.at n=5A223312
- Number of nX6 0..1 arrays with successive rows and columns fitting to straight lines with nondecreasing slope, with a single point array taken as having zero slope.at n=2A223315
- T(n,k)=Number of nXk 0..1 arrays with successive rows and columns fitting to straight lines with nondecreasing slope, with a single point array taken as having zero slope.at n=30A223317