Properties of the Number 1321

One Thousand Three Hundred Twenty-One

Basics

Value: 1320 → 1321 → 1322

Parity: odd

Prime: Yes

Previous Prime: 1319

Next Prime: 1327

Digit Sum: 7

Digital Root: 7

Palindrome: No

Factorization: 1321

Divisors: 1, 1321

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 10100101001

Octal: 2451

Duodecimal: 921

Hexadecimal: 529

Square: 1745041

Square Root: 36.345563690772494

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

Greater of twin primes. A6512

Integers written in factorial base. A7623

Number of partitions of n into parts 5k+2 or 5k+3. A3106

Primes p such that (p+1)/2 is prime. A5383

Primes of form 8n+1, that is, primes congruent to 1 mod 8. A7519

Primes whose binary representation is also the decimal representation of a prime. A65720

Flavius Josephus's sieve: Start with the natural numbers; at the k-th sieving step, remove every (k+1)-st term of the sequence remaining after the (k-1)-st sieving step; iterate. A960

Numbers k such that (27^k - 2^k)/25 is prime. A377031

Primes whose base-2 representation is also the base-3 representation of a prime. A235266

Primes whose decimal representation is a valid number in base 9 and interpreted as such is again a prime. A235395