285690 has 32 divisors (see below), whose sum is σ = 699840. Its totient is φ = 74624.

The previous prime is 285673. The next prime is 285697. The reversal of 285690 is 96582.

It is a super-2 number, since 2×285690² = 163237552200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a d-powerful number, because it can be written as 2¹⁰ + 8⁴ + 6⁷ + 5⁴ + 9 + 0 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (285697) by changing a digit.

285690 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, 2617 + ... + 2723.

It is an arithmetic number, because the mean of its divisors is an integer number (21870).

2²⁸⁵⁶⁹⁰ is an apocalyptic number.

It is a pronic number, being equal to 534×535.

285690 is an abundant number, since it is smaller than the sum of its proper divisors (414150).

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

285690 is a wasteful number, since it uses less digits than its factorization.

285690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 285690 is about 534.4997661365. The cubic root of 285690 is about 65.8615094190.

The spelling of 285690 in words is "two hundred eighty-five thousand, six hundred ninety".