7997
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 32
- Digital Root
- 5
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8736
- Proper Divisor Sum (Aliquot Sum)
- 739
- 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
- 7260
- Möbius Function
- 1
- Radical
- 7997
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 52
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Shifts 4 places right under inverse binomial transform.at n=12A010748
- a(n) = floor( n*(n-1)*(n-2)/27 ).at n=61A011909
- Palindromic in bases 4 and 10.at n=11A029961
- a(n) = C(n+3,4) + 3*C(n+1,3) + 5*C(n-1,2) + 7*n - 15.at n=15A034858
- a(n) = C(n+3,4) + 3*C(n+1,3) + 5*C(n-1,2) + 7*n - 15 for n >= 3; a(1)=1, a(2)=10.at n=16A034859
- Base-10 palindromes that start with 7.at n=21A043042
- Largest palindromic substring in 6^n.at n=35A046264
- Palindromes with exactly 2 prime factors (counted with multiplicity).at n=46A046328
- Palindromes with exactly 2 palindromic prime factors (counted with multiplicity), and no other prime factors.at n=22A046376
- Palindromes with exactly 2 distinct prime factors.at n=43A046392
- Palindromes with exactly 2 distinct palindromic prime factors.at n=19A046408
- Palindromes expressible as sum of 2 consecutive palindromes.at n=52A046497
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 14.at n=34A050963
- Nonnegative numbers of the form n^3 (+/-) 3, n >= 0.at n=38A052276
- Sum of digits = 8 times number of digits.at n=23A061425
- Smallest palindrome with digit sum = n.at n=32A062388
- a(n) = C(n+6, 6) - n - 1.at n=10A062989
- n sets a new record for the number of integers k such that n = k + reverse(k).at n=27A067035
- Concatenation of n-th prime and its reverse.at n=21A067087
- Palindromic odd squarefree numbers with an even number of distinct prime factors.at n=37A075810