285506 has 16 divisors (see below), whose sum is σ = 470400. Its totient is φ = 129168.

The previous prime is 285497. The next prime is 285517. The reversal of 285506 is 605582.

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 285506.

It is an unprimeable number.

285506 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 7 ways as a sum of consecutive naturals, for example, 1985 + ... + 2123.

It is an arithmetic number, because the mean of its divisors is an integer number (29400).

2²⁸⁵⁵⁰⁶ is an apocalyptic number.

285506 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

285506 is a deficient number, since it is larger than the sum of its proper divisors (184894).

285506 is a wasteful number, since it uses less digits than its factorization.

285506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 285506 is about 534.3276148582. The cubic root of 285506 is about 65.8473669098.

The spelling of 285506 in words is "two hundred eighty-five thousand, five hundred six".