Properties of the Number 61985

Sixty-One Thousand Nine Hundred Eighty-Five

Basics

Value: 61984 → 61985 → 61986

Parity: odd

Prime: No

Previous Prime: 61981

Next Prime: 61987

Digit Sum: 29

Digital Root: 2

Palindrome: No

Factorization: 5 × 7 ² × 11 × 23

Divisors: 1, 5, 7, 11, 23, 35, 49, 55, 77, 115

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1111001000100001

Octal: 171041

Duodecimal: 2BA55

Hexadecimal: f221

Square: 3842140225

Square Root: 248.96786941290236

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

a(n) = (16/3) * squared area of a triangle with sides prime(n), prime(n+1), and prime(n+2). A330096

Number of vertices in the hyperoctahedral (or cocktail party) graph of order n. A368756

a(n) = A000265(A263931(n)). A356637

Occurrences of decrease of the probability density P(n) of coprime numbers k,m, satisfying 1 <= k <= a(n) and 1 <= m <= a(n), and a(n) congruent to 1 (mod 2) and a(n) not congruent to 3 (mod 6). A280879

Numbers of the form 49·k, where 49·k+2 and 49·k-6 are both prime. A153779

Expansion of x*(1 + 4·x + x²)/((1 - x)⁵*(1 + x)⁴). A290055

Irregular triangle read by rows, arising from Garvan's proof of Watson's generalization of Ramanujan's partition congruences for powers of 7. A330329

Triangle, read by rows, where T(n,k) = T(n-1,k-1) + 2·T(n,k-1) when k > 0, else T(n,0) = T(n-1,n-1) when n > 0, with T(0,0) = 1. A376177

O.g.f. A(x) satisfies: 0 = [xⁿ] exp( n² * Integral A(x)⁴ dx ) / A(x), for n > 0. A305143

Triangle read by rows: T(n,k) = 7·binomial(n,k) for 1 <= k <= n with T(n,n) = 1 for n >= 0. A131115