28387860 has 96 divisors (see below), whose sum is σ = 82736640. Its totient is φ = 7268352.

The previous prime is 28387787. The next prime is 28387861. The reversal of 28387860 is 6878382.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28387861) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 251164 + ... + 251276.

It is an arithmetic number, because the mean of its divisors is an integer number (861840).

Almost surely, 2^28387860 is an apocalyptic number.

28387860 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 28387860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41368320).

28387860 is an abundant number, since it is smaller than the sum of its proper divisors (54348780).

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

28387860 is a wasteful number, since it uses less digits than its factorization.

28387860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257 (or 255 counting only the distinct ones).

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

The square root of 28387860 is about 5328.0259008379. The cubic root of 28387860 is about 305.0545812916.

The spelling of 28387860 in words is "twenty-eight million, three hundred eighty-seven thousand, eight hundred sixty".