285740 has 48 divisors (see below), whose sum is σ = 743232. Its totient is φ = 89856.

The previous prime is 285731. The next prime is 285749. The reversal of 285740 is 47582.

285740 = T₁₉₅ + T₁₉₆ + ... + T₂₀₈.

It is an interprime number because it is at equal distance from previous prime (285731) and next prime (285749).

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285749) by changing a digit.

285740 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1742 + ... + 1898.

It is an arithmetic number, because the mean of its divisors is an integer number (15484).

2²⁸⁵⁷⁴⁰ is an apocalyptic number.

285740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 285740, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (371616).

285740 is an abundant number, since it is smaller than the sum of its proper divisors (457492).

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

285740 is a wasteful number, since it uses less digits than its factorization.

285740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 285740 is about 534.5465367954. The cubic root of 285740 is about 65.8653514428.

The spelling of 285740 in words is "two hundred eighty-five thousand, seven hundred forty".