1977
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 2640
- Proper Divisor Sum (Aliquot Sum)
- 663
- 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
- 1316
- Möbius Function
- 1
- Radical
- 1977
- 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
- 143
- 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
- Expansion of (psi(x^2) / psi(-x))^3 in powers of x where psi() is a Ramanujan theta function.at n=10A001937
- a(n) = ceiling(n*phi^9), where phi is the golden ratio, A001622.at n=26A004964
- Crystal ball sequence for planar net 4.8.8.at n=38A008577
- a(n) = n^2 + 3*n - 1.at n=43A014209
- Expansion of (1+x)/(1-x-x^2-x^4-x^5).at n=13A014743
- Quadruples of different integers from [ 1,n ] with no common factors between triples.at n=17A015625
- Quadruples of different integers from [ 2,n ] with no common factors between triples.at n=17A015629
- Numbers k such that the continued fraction for sqrt(k) has period 28.at n=34A020367
- a(0)=0, a(2*n) = 2*a(n) + 2*a(n-1) + n^2 + n, a(2*n+1) = 4*a(n) + (n+1)^2.at n=37A022560
- Number of partitions of n with distinct parts p(i) such that if i != j, then |p(i) - p(j)| >= 3.at n=66A025157
- Index of 10^n within the sequence of the numbers of the form 4^i*10^j.at n=48A025742
- Sequence satisfies T(a)=a, where T is defined below.at n=40A027597
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 28.at n=24A031526
- Lucky numbers with size of gaps equal to 12 (upper terms).at n=23A031895
- a(n) = a(n-1)+ a(round(2*(n-1)/3)) +a(round((n-1)/3)) starting a(1)=1.at n=21A033498
- Smallest number that takes n steps to reach 0 under "k->min product of 2 numbers whose concatenation is k".at n=9A035933
- Denominators of continued fraction convergents to sqrt(33).at n=8A041055
- Numbers k such that string 2,3 occurs in the base 7 representation of k but not of k-1.at n=46A044155
- Numbers n such that string 7,1 occurs in the base 8 representation of n but not of n-1.at n=33A044244
- Numbers n such that string 3,6 occurs in the base 9 representation of n but not of n-1.at n=27A044284