Properties of the Number 425

Four Hundred Twenty-Five

Basics

Value: 424 → 425 → 426

Parity: odd

Prime: No

Previous Prime: 421

Next Prime: 431

Digit Sum: 11

Digital Root: 2

Palindrome: No

Factorization: 5 ² × 17

Divisors: 1, 5, 17, 25, 85, 425

Polygonal

Triangular: No

Square: No

Pentagonal: Yes

Hexagonal: No

Heptagonal: No

Tetrahedral: No

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Representations

Binary: 110101001

Octal: 651

Duodecimal: 2B5

Hexadecimal: 1a9

Square: 180625

Square Root: 20.615528128088304

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

Pentagonal numbers: a(n) = n*(3·n-1)/2. A326

Generalized pentagonal numbers: m*(3·m - 1)/2, m = 0, +-1, +-2, +-3, .... A1318

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

Number of nonempty subsets of {1,2,3,...,n} whose elements have an integer average. A51293

Numbers which are the product of a prime and the square of a different prime (p² * q). A54753

Number of partitions of n into distinct parts in which the number of parts divides n. A102627

Expansion of g.f. x/((1 - x)²*(1 - x³)). A1840

Centered tetrahedral numbers. A5894

Total number of odd entries in first n rows of Pascal's triangle: a(0) = 0, a(1) = 1, a(2k) = 3·a(k), a(2k+1) = 2·a(k) + a(k+1). a(n) = ∑_i=0..n-1 2^wt(i). A6046

a(n) = 8·n + 1. A17077