285257280 has 448 divisors, whose sum is σ = 1200863232. Its totient is φ = 55541760.

The previous prime is 285257243. The next prime is 285257299. The reversal of 285257280 is 82752582.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (448).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1256527 + ... + 1256753.

Almost surely, 2^285257280 is an apocalyptic number.

285257280 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 285257280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (600431616).

285257280 is an abundant number, since it is smaller than the sum of its proper divisors (915605952).

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

285257280 is a wasteful number, since it uses less digits than its factorization.

285257280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 272 counting only the distinct ones).

The product of its (nonzero) digits is 89600, while the sum is 39.

The square root of 285257280 is about 16889.5612731651. The cubic root of 285257280 is about 658.2824026543.

The spelling of 285257280 in words is "two hundred eighty-five million, two hundred fifty-seven thousand, two hundred eighty".