285978 has 32 divisors (see below), whose sum is σ = 714240. Its totient is φ = 74160.

The previous prime is 285977. The next prime is 285979. The reversal of 285978 is 879582.

It is an interprime number because it is at equal distance from previous prime (285977) and next prime (285979).

It is a nialpdrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (285977) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 153 + ... + 771.

It is an arithmetic number, because the mean of its divisors is an integer number (22320).

2²⁸⁵⁹⁷⁸ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 285978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (357120).

285978 is an abundant number, since it is smaller than the sum of its proper divisors (428262).

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

285978 is a wasteful number, since it uses less digits than its factorization.

285978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642.

The product of its digits is 40320, while the sum is 39.

The square root of 285978 is about 534.7691090555. The cubic root of 285978 is about 65.8836333347.

It can be divided in two parts, 28 and 5978, that added together give a palindrome (6006).

The spelling of 285978 in words is "two hundred eighty-five thousand, nine hundred seventy-eight".