Properties of the Number 667

Six Hundred Sixty-Seven

Basics

Value: 666 → 667 → 668

Parity: odd

Prime: No

Previous Prime: 661

Next Prime: 673

Digit Sum: 19

Digital Root: 1

Palindrome: No

Factorization: 23 × 29

Divisors: 1, 23, 29, 667

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 1010011011

Octal: 1233

Duodecimal: 477

Hexadecimal: 29b

Square: 444889

Square Root: 25.826343140289914

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

Numbers k such that (35·10^k - 11)/3 is prime. A268448

Central polygonal numbers (the Lazy Caterer's sequence): n(n+1)/2 + 1; or, maximal number of pieces formed when slicing a pancake with n cuts. A124

Products of 2 successive primes. A6094

Brilliant numbers: semiprimes (products of two primes, A001358) whose prime factors have the same number of decimal digits. A78972

Prime shift array: Square array read by antidiagonals: A(1,col) = 2·col, and for row > 1, A(row,col) = A003961(A(row-1,col)). A246278

Sieve of Eratosthenes arranged as an array and read by antidiagonals as A(1,1), A(1,2), A(2,1), A(1,3), A(2,2), A(3,1), ... A83221

Indices k such that (1/3)*(prime(k)+prime(k+1)+prime(k+2)) is a prime. A64113

Number of partitions of n into at least two distinct parts. A111133

The "comma sequence": the lexicographically earliest sequence of positive numbers with the property that the sequence formed by the pairs of digits adjacent to the commas between the terms is the same as the sequence of successive differences between the terms. A121805

Sieve of Eratosthenes arranged as an array and read by antidiagonals in the up direction; n-th row has property that smallest prime factor is prime(n). A83140