7645
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 10080
- Proper Divisor Sum (Aliquot Sum)
- 2435
- 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
- 5520
- Möbius Function
- -1
- Radical
- 7645
- 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
- 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
- 31
- 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
- Central factorial numbers: A008955(n,3).at n=2A000597
- Central factorial numbers: 2nd subdiagonal of A008955.at n=3A001820
- Number of loopless tree-rooted planar maps with 3 vertices and n faces and no isthmuses.at n=9A006428
- Coordination sequence T2 for Coesite.at n=46A008268
- Triangle of central factorial numbers |t(2n,2n-2k)| read by rows.at n=18A008955
- cos(arctanh(x)+log(x+1))=1-4/2!*x^2+6/3!*x^3-19/4!*x^4+20/5!*x^5...at n=8A013160
- Number of partitions of n into 9 unordered relatively prime parts.at n=36A023029
- Numbers with exactly 7 1's in their ternary expansion.at n=20A023698
- [ exp(5/12)*n! ].at n=6A030936
- Numbers in which all pairs of consecutive base-4 digits differ by 2.at n=18A033082
- Base-4 digits are, in order, the first n terms of the periodic sequence with initial period 1,3.at n=6A037576
- Sums of 7 distinct powers of 3.at n=12A038469
- Numerators of continued fraction convergents to sqrt(341).at n=6A041644
- Numbers whose base-4 representation contains exactly four 1's and three 3's.at n=14A045132
- a(0) = 1; a(n) is obtained by incrementing each digit of a(n-1) by 3.at n=8A061515
- G.f.: A(x) = exp(sum(n>=1, A084250(n)*x^n/n)), where A084250 lists the least distinct positive integers that allow A(x) to be an integer power series.at n=32A084251
- Decimal representation of n-th iteration of the Rule 158 elementary cellular automaton starting with a single black cell.at n=6A118171
- Decimal representation of n-th iteration of the Rule 188 elementary cellular automaton starting with a single black cell.at n=12A118173
- Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1000-1111-1000 pattern in any orientation.at n=11A146414
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 1, -1), (0, 1, 1), (1, 0, 1)}.at n=7A150538