285255581 has 12 divisors (see below), whose sum is σ = 312369876. Its totient is φ = 258952320.

The previous prime is 285255559. The next prime is 285255599. The reversal of 285255581 is 185552582.

It can be written as a sum of positive squares in 6 ways, for example, as 78039556 + 207216025 = 8834^2 + 14395^2 .

It is not a de Polignac number, because 285255581 - 2¹⁴ = 285239197 is a prime.

It is a super-2 number, since 2×285255581² = 162741492983295122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285255511) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45425 + ... + 51321.

It is an arithmetic number, because the mean of its divisors is an integer number (26030823).

Almost surely, 2^285255581 is an apocalyptic number.

It is an amenable number.

285255581 is a deficient number, since it is larger than the sum of its proper divisors (27114295).

285255581 is an equidigital number, since it uses as much as digits as its factorization.

285255581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6032 (or 5971 counting only the distinct ones).

The product of its digits is 160000, while the sum is 41.

The square root of 285255581 is about 16889.5109757506. The cubic root of 285255581 is about 658.2810957359.

The spelling of 285255581 in words is "two hundred eighty-five million, two hundred fifty-five thousand, five hundred eighty-one".