Properties of the Number 61561

Sixty-One Thousand Five Hundred Sixty-One

Basics

Value: 61560 → 61561 → 61562

Parity: odd

Prime: Yes

Previous Prime: 61559

Next Prime: 61583

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 61561

Divisors: 1, 61561

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1111000001111001

Octal: 170171

Duodecimal: 2B761

Hexadecimal: f079

Square: 3789756721

Square Root: 248.114892741246

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

Primes whose base-3 representation also is the base-2 representation of a prime. A235265

Primes p such that (p+1)/2, (p+2)/3 and (p+3)/4 are also primes. A163573

Primes having only {1, 5, 6} as digits. A385779

T(n,k)=Number of nXk 0..1 arrays with every element equal to 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. A300546

Numbers k such that τ(k) + τ(k+1) + τ(k+2) + τ(k+3) = 16, where τ is the number of divisors function A000005. A350686

a(n) = A273059(4n+3). A275919

Numbers k such that -3 is a quadratic residue (not necessarily coprime) modulo k, k + 1, k + 2 and k + 3. A318527

Lexicographically earliest sequence of prime numbers whose partial products, starting from the second, are all Fermat pseudoprimes to base 2 (A001567). A374028

Lexicographically earliest strictly increasing sequence of prime numbers whose partial products, starting from the second, are all Fermat pseudoprimes to base 2 (A001567). A374029

a(n) = coefficient of the term that is independent of 2^1/3 and 2^2/3 in the expansion of (1 + 2^1/3 + 2^2/3)ⁿ. A377314