Properties of the Number -1421

Four Hundred Twenty-One

Basics

Value: -1422 → -1421 → -1420

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 8

Digital Root: 8

Palindrome: No

Factorization: 7 ² × 29

Divisors: 1, 7, 29, 49, 203, 1421

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: -10110001101

Octal: -2615

Duodecimal: -9A5

Hexadecimal: -58d

Square: 2019241

Square Root: 37.69615364994153

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, read by rows, where all columns of T are different and yet all columns of the matrix square T² (A118407) are equal; also equals the matrix inverse of triangle A118400. A118404

O.g.f. A(x) satisfies: [xⁿ] exp( n·x*A(x) ) * (n+1 - n·A(x)) = 0 for n >= 1. A317338

a(n) = n! * ∑_k=0..n (-1)^n-k * k⁴ / k!. A368717

Triangle read by rows: T(n,k) gives n! times the coefficient of x^k in the polynomial that describes the number of permutations on·letters with major index n. A342645

Odd numbers of the form p^1+4k * r², where p is prime of the form 1+4m, r > 1, and gcd(p,r) = 1. (Euler's criteria for odd perfect numbers). A228058

Positive numbers for which the sum of digits equals the product of digits. A34710

Triangle read by rows: T(n,c) = number of successive equalities in set partitions of n. A56857

a(n) = n*(n+9)/2. A56000

Mountain numbers. A134941

Number of integer partitions of n whose length cannot be written as a nonnegative linear combination of the distinct parts. A367219