285220685 has 12 divisors (see below), whose sum is σ = 361229148. Its totient is φ = 216165888.

The previous prime is 285220673. The next prime is 285220697. The reversal of 285220685 is 586022582.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (285220673) and next prime (285220697).

It can be written as a sum of positive squares in 2 ways, for example, as 140114569 + 145106116 = 11837^2 + 12046^2 .

It is not a de Polignac number, because 285220685 - 2¹⁰ = 285219661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 77204 + ... + 80813.

It is an arithmetic number, because the mean of its divisors is an integer number (30102429).

Almost surely, 2^285220685 is an apocalyptic number.

It is an amenable number.

285220685 is a deficient number, since it is larger than the sum of its proper divisors (76008463).

285220685 is a wasteful number, since it uses less digits than its factorization.

285220685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 158060 (or 158041 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 38.

The square root of 285220685 is about 16888.4778769432. The cubic root of 285220685 is about 658.2542516056.

The spelling of 285220685 in words is "two hundred eighty-five million, two hundred twenty thousand, six hundred eighty-five".