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Properties of the Number 21143

Twenty-One Thousand One Hundred Forty-Three

Basics

Value: 21142 → 21143 → 21144

Parity: odd

Prime: Yes

Previous Prime: 21139

Next Prime: 21149

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 21143

Divisors: 1, 21143

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2730 Try Today's Challenge

Representations

Binary: 101001010010111

Octal: 51227

Duodecimal: 1029B

Hexadecimal: 5297

Square: 447026449

Square Root: 145.40632723509663

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

The array in A059216 read by antidiagonals in 'up' direction. A59217
Primes whose decimal representation is a valid number in base 5 and interpreted as such is again a prime. A90708
Numbers k such that (2k - k)*2k + 1 is prime. A200816
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
Number of set partitions of [n] with alternating parity of elements. A274547
Primes of the form p = prime(k+1) such that prime(k) = (prime(k+3)+prime(k-1))/2. A126239
Primes p such that continued fraction of (1 + sqrt(p))/2 has period 16 : primes in A146339. A146361
a(n) = 22·n2 + 1. A158537
a(n) is the least number such that d(a(n)) = d(R(a(n)))/n, where R(n) is the digit reverse of n and d(n) is the number of divisors of n. A284495
The prime numbers whose digit sum, adjacent digit sum concatenation, and adjacent digit difference concatenation are also primes. A330653