7503
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 10416
- Proper Divisor Sum (Aliquot Sum)
- 2913
- 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
- 4800
- Möbius Function
- -1
- Radical
- 7503
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- yes
- 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
- 62
- Smith Number
- yes
- 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
- Crystal ball sequence for squashed {D_5}^* lattice, perhaps the smallest example of a "non-superficial" lattice.at n=6A010025
- Numbers k such that 227*2^k+1 is prime.at n=11A032490
- In A015922, not in A033553.at n=19A033554
- a(n) = (2*n-1)*(4*n-1).at n=31A033567
- Triangular numbers that have some nontrivial permutation of digits which is also triangular.at n=32A034291
- a(n) = a(n-1) + n^2 if n prime else a(n-1) - n, starting with a(0) = 0.at n=45A051353
- a(n) = 49*(n*(n+1)/2) + 6.at n=17A061792
- a(n) = 25*n*(n + 1)/2 + 3.at n=24A061793
- 3 times pentagonal numbers: 3*n*(3*n-1)/2.at n=41A062741
- Triangular numbers with sum of digits = 15.at n=21A068130
- a(n) = smallest triangular number having no digit in common with the previous term, with a(1) = 1.at n=23A068818
- Numbers m such that [A070080(m), A070081(m), A070082(m)] is an acute scalene integer triangle with prime side lengths.at n=18A070123
- Triangular numbers that are 3-almost primes.at n=36A075875
- Triangular numbers whose sum of prime factors (with repetition) is also triangular.at n=14A076169
- Positive integers not expressible as the sum of a prime and a triangular number.at n=48A076768
- Triangular numbers m such that A040115(m) is also triangular.at n=20A087597
- Largest n-digit term of A087597, or 0 if no such number exists.at n=3A087600
- Smith triangular numbers.at n=5A098840
- a(n) = Sum_{k=0..floor(n/2)} C(n-k,k+2)*3^(n-k-2)*(4/3)^k.at n=7A099624
- Expansion of 1/(1-x-2*x^2-3*x^3).at n=11A101822