Properties of the Number 71780

Seventy-One Thousand Seven Hundred Eighty

Basics

Value: 71779 → 71780 → 71781

Parity: even

Prime: No

Previous Prime: 71777

Next Prime: 71789

Digit Sum: 23

Digital Root: 5

Palindrome: No

Factorization: 2 ² × 5 × 37 × 97

Divisors: 1, 2, 4, 5, 10, 20, 37, 74, 97, 148

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10001100001100100

Octal: 214144

Duodecimal: 35658

Hexadecimal: 11864

Square: 5152368400

Square Root: 267.9178978717174

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Number of ways to toss a coin n times and not get a run of four. A135491

a(n) = 5*(3·n+1)*(9·n+8)/2 (n>=0). A304508

Consider the sequence of 4-tuples {0,a,b,c} (c>=a+b; a,b,c>0) which have the smallest integer 'c' required to reach {k,k,k,k} in n steps under map {r,s,t,u}->{|r-s|,|s-t|,|t-u|,|u-r|}. This sequence gives the third term 'b' of these quadruples. A34804

First differences of A000213, also twice A000073. A354784

Number of nX5 0..1 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards. A281762

Smallest k > n such that there are exactly n pairs (x,y) (1 <= x <= y <= k) solutions of the equation: φ(xy)=σ(x)+σ(y). A71780