285140 has 24 divisors (see below), whose sum is σ = 612360. Its totient is φ = 111488.

The previous prime is 285139. The next prime is 285151. The reversal of 285140 is 41582.

It can be written as a sum of positive squares in 4 ways, for example, as 8464 + 276676 = 92^2 + 526^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 926 + ... + 1194.

It is an arithmetic number, because the mean of its divisors is an integer number (25515).

2²⁸⁵¹⁴⁰ is an apocalyptic number.

285140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

285140 is an abundant number, since it is smaller than the sum of its proper divisors (327220).

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

285140 is a wasteful number, since it uses less digits than its factorization.

285140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331 (or 329 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 285140 is about 533.9850185164. The cubic root of 285140 is about 65.8192175401.

The spelling of 285140 in words is "two hundred eighty-five thousand, one hundred forty".