285240 has 32 divisors (see below), whose sum is σ = 856080. Its totient is φ = 76032.

The previous prime is 285227. The next prime is 285251. The reversal of 285240 is 42582.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1069 + ... + 1308.

2²⁸⁵²⁴⁰ is an apocalyptic number.

285240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

285240 is an abundant number, since it is smaller than the sum of its proper divisors (570840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

285240 is a wasteful number, since it uses less digits than its factorization.

285240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2391 (or 2387 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 285240 is about 534.0786458940. The cubic root of 285240 is about 65.8269110151.

It can be divided in two parts, 285 and 240, that added together give a palindrome (525).

The spelling of 285240 in words is "two hundred eighty-five thousand, two hundred forty".