285612309 has 12 divisors (see below), whose sum is σ = 419315052. Its totient is φ = 187286400.

The previous prime is 285612277. The next prime is 285612319. The reversal of 285612309 is 903216582.

285612309 is a `hidden beast` number, since 2 + 8 + 5 + 612 + 30 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 160731684 + 124880625 = 12678^2 + 11175^2 .

It is not a de Polignac number, because 285612309 - 2⁵ = 285612277 is a prime.

It is a super-2 number, since 2×285612309² = 163148782104622962, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285612319) 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, 259572 + ... + 260669.

It is an arithmetic number, because the mean of its divisors is an integer number (34942921).

Almost surely, 2^285612309 is an apocalyptic number.

It is an amenable number.

285612309 is a deficient number, since it is larger than the sum of its proper divisors (133702743).

285612309 is a wasteful number, since it uses less digits than its factorization.

285612309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520308 (or 520305 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 285612309 is about 16900.0683134714. The cubic root of 285612309 is about 658.5553871598. Note that the first 3 decimals are identical.

The spelling of 285612309 in words is "two hundred eighty-five million, six hundred twelve thousand, three hundred nine".