285138620 has 96 divisors (see below), whose sum is σ = 705148416. Its totient is φ = 95846400.

The previous prime is 285138619. The next prime is 285138649. The reversal of 285138620 is 26831582.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 135980 + ... + 138060.

It is an arithmetic number, because the mean of its divisors is an integer number (7345296).

Almost surely, 2^285138620 is an apocalyptic number.

285138620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 285138620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (352574208).

285138620 is an abundant number, since it is smaller than the sum of its proper divisors (420009796).

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

285138620 is a wasteful number, since it uses less digits than its factorization.

285138620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2151 (or 2149 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 35.

The square root of 285138620 is about 16886.0480871043. The cubic root of 285138620 is about 658.1911135752.

The spelling of 285138620 in words is "two hundred eighty-five million, one hundred thirty-eight thousand, six hundred twenty".