285971840 has 192 divisors, whose sum is σ = 868611600. Its totient is φ = 89026560.

The previous prime is 285971837. The next prime is 285971849. The reversal of 285971840 is 48179582.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 285971791 and 285971800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285971849) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 344546 + ... + 345374.

Almost surely, 2^285971840 is an apocalyptic number.

285971840 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 285971840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (434305800).

285971840 is an abundant number, since it is smaller than the sum of its proper divisors (582639760).

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

285971840 is a wasteful number, since it uses less digits than its factorization.

285971840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 873 (or 854 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 44.

The square root of 285971840 is about 16910.7019369392. The cubic root of 285971840 is about 658.8316028422.

The spelling of 285971840 in words is "two hundred eighty-five million, nine hundred seventy-one thousand, eight hundred forty".