Properties of the Number 20719

Twenty Thousand Seven Hundred Nineteen

Basics

Value: 20718 → 20719 → 20720

Parity: odd

Prime: Yes

Previous Prime: 20717

Next Prime: 20731

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 20719

Divisors: 1, 20719

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 101000011101111

Octal: 50357

Duodecimal: BBA7

Hexadecimal: 50ef

Square: 429276961

Square Root: 143.94096011907104

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

Triangle T(n, k, m) = (m*(n-k) + 1)*T(n-1, k-1, m) + (m·k + 1)*T(n-1, k, m) + m·k*(n-k)*T(n-2, k-1, m) with T(n, 0, m) = T(n, n, m) = 1 and m = 2, read by rows. A157148

Primes p such that p, p+12, p+24 are consecutive primes. A52188

Prime time primes (of the form HMMSS with primes H < 24 and MM, SS < 60) such that the corresponding number of seconds after midnight is also prime. A295000

Numbers of the form HMMSS with primes H < 24 and MM, SS < 60, for which the number of seconds after midnight, 3600·H+60·MM+SS, is also prime. A295011

Prime time primes on 6-digit clocks, second definition: primes of the form HMMSS where H, MM, SS are primes, H < 24, MM and SS < 60. A295013

G.f. A(x) satisfies A(x) = Series_Reversion(x - x³*A'(x)⁴). A361307

Primes p such that x³⁶ = 2 has no solution mod p, but x¹² = 2 has a solution mod p. A59668

Denominators of continued fraction convergents to sqrt(828). A42599

Indices of primes in sequence defined by A(0) = 99, A(n) = 10·A(n-1) - 1 for n > 0. A56266

Largest primes of 'a' consecutive primes whose sum is a prime in A152471. A152472