Properties of the Number 21977

Twenty-One Thousand Nine Hundred Seventy-Seven

Basics

Value: 21976 → 21977 → 21978

Parity: odd

Prime: Yes

Previous Prime: 21961

Next Prime: 21991

Digit Sum: 26

Digital Root: 8

Palindrome: No

Factorization: 21977

Divisors: 1, 21977

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

2196 Try Today's Challenge

Representations

Binary: 101010111011001

Octal: 52731

Duodecimal: 10875

Hexadecimal: 55d9

Square: 482988529

Square Root: 148.24641648282767

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 p such that p-1 and p+1 each contain at least one cubed prime in their prime factorization. A162870

Number of binary necklaces with n beads and at least three consecutive black beads. A351360

Primes of the form 666·k - 1. A63472

Primes of the form (2+n)*(1+2·n)+(1+n)*(2+2·n). A171748

Complement of A381767. A382131

Partial sums of A048655. A48746

Concatenation of n³ and 7. A61679

Numbers k such that the continued fraction for sqrt(k) has period 81. A20420

Smallest nontrivial extension of n-th cube which is a prime. A30692

Let s(k) denote the k-th term of an integer sequence such that s(0)=0 and s(i) for all i>0 is the least natural number such that no four elements of {s(0),..,s(i)} are in arithmetic progression. Then it appears that there are many set of 3 consecutive integers in s(k). Sequence gives the smallest element in those triples. A71711