287816640 has 112 divisors (see below), whose sum is σ = 919630368. Its totient is φ = 76263424.

The previous prime is 287816629. The next prime is 287816689. The reversal of 287816640 is 46618782.

287816640 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 287816592 and 287816601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 165214 + ... + 166946.

Almost surely, 2^287816640 is an apocalyptic number.

287816640 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 287816640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (459815184).

287816640 is an abundant number, since it is smaller than the sum of its proper divisors (631813728).

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

287816640 is a wasteful number, since it uses less digits than its factorization.

287816640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1926 (or 1916 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 42.

The square root of 287816640 is about 16965.1595925296. The cubic root of 287816640 is about 660.2452715581.

The spelling of 287816640 in words is "two hundred eighty-seven million, eight hundred sixteen thousand, six hundred forty".