285621 has 24 divisors (see below), whose sum is σ = 465120. Its totient is φ = 155232.

The previous prime is 285613. The next prime is 285629. The reversal of 285621 is 126582.

It is an interprime number because it is at equal distance from previous prime (285613) and next prime (285629).

It is not a de Polignac number, because 285621 - 2³ = 285613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 285591 and 285600.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 285621.

It is not an unprimeable number, because it can be changed into a prime (285629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4230 + ... + 4296.

It is an arithmetic number, because the mean of its divisors is an integer number (19380).

2²⁸⁵⁶²¹ is an apocalyptic number.

285621 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

285621 is a deficient number, since it is larger than the sum of its proper divisors (179499).

285621 is a wasteful number, since it uses less digits than its factorization.

285621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113 (or 106 counting only the distinct ones).

The product of its digits is 960, while the sum is 24.

The square root of 285621 is about 534.4352159055. The cubic root of 285621 is about 65.8562066899.

The spelling of 285621 in words is "two hundred eighty-five thousand, six hundred twenty-one".