Properties of the Number 81551

Eighty-One Thousand Five Hundred Fifty-One

Basics

Value: 81550 → 81551 → 81552

Parity: odd

Prime: Yes

Previous Prime: 81547

Next Prime: 81553

Digit Sum: 20

Digital Root: 2

Palindrome: No

Factorization: 81551

Divisors: 1, 81551

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10011111010001111

Octal: 237217

Duodecimal: 3B23B

Hexadecimal: 13e8f

Square: 6650565601

Square Root: 285.57135710711606

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 having only {1, 5, 8} as digits. A385780

Primes of the form T(k) + S(k) + 1 where T(k) is the k-th triangular number and S(k) is the k-th square number. A229080

Primes p such that continued fraction of (1 + sqrt(p))/2 has period 8; primes in A146333. A146353

Primes p such that the differences between the 5 consecutive primes starting with p are (2,6,4,6). A78949

Numbers k such that k and k² use only the digits 0, 1, 5, 6 and 8. A136870

Primes in A343531. A343532

Prime numbers such that the product of their digits equals twice the number of their digits times the sum of their digits. A343701

Primes p such that there are exactly p solutions to y² + x·y + y == x³ + x² - 10·x - 10 (mod p). A275777

Triangle, read by rows, in which the n-th row contains n smallest n-digit numbers. A81551