284521 has 2 divisors, whose sum is σ = 284522. Its totient is φ = 284520.

The previous prime is 284509. The next prime is 284527. The reversal of 284521 is 125482.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 168921 + 115600 = 411^2 + 340^2 .

It is a cyclic number.

It is not a de Polignac number, because 284521 - 2⁵ = 284489 is a prime.

It is a Chen prime.

284521 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 284492 and 284501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (284527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 142260 + 142261.

It is an arithmetic number, because the mean of its divisors is an integer number (142261).

2²⁸⁴⁵²¹ is an apocalyptic number.

It is an amenable number.

284521 is a deficient number, since it is larger than the sum of its proper divisors (1).

284521 is an equidigital number, since it uses as much as digits as its factorization.

284521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 640, while the sum is 22.

The square root of 284521 is about 533.4050993382. The cubic root of 284521 is about 65.7715548561.

Subtracting from 284521 its product of digits (640), we obtain a triangular number (283881 = T₇₅₃).

The spelling of 284521 in words is "two hundred eighty-four thousand, five hundred twenty-one".