Properties of the Number 401

Four Hundred One

Basics

Value: 400 → 401 → 402

Parity: odd

Prime: Yes

Previous Prime: 397

Next Prime: 409

Digit Sum: 5

Digital Root: 5

Palindrome: No

Factorization: 401

Divisors: 1, 401

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110010001

Octal: 621

Duodecimal: 295

Hexadecimal: 191

Square: 160801

Square Root: 20.024984394500787

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: Yes

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Primes of the form x² + xy + 2y², with·and y nonnegative. A106856

Pythagorean primes: primes of the form 4·k + 1. A2144

a(n) = n² + 1. A2522

Prime-indexed primes: primes with prime subscripts. A6450

Primes of the form k² + 1. A2496

n written in primorial base. A49345

Ramanujan primes R_n: a(n) is the smallest number such that if x >= a(n), then π(x) - π(x/2) >= n, where π(x) is the number of primes <= x. A104272

Numbers k that divide the (left) concatenation of all numbers <= k written in base 25 (most significant digit on left). A29494

Primes congruent to 1 or 2 modulo 4; or, primes of form x² + y²; or, -1 is a square mod p. A2313

Primes of the form 3n-1. A3627