28981584 has 80 divisors (see below), whose sum is σ = 84419200. Its totient is φ = 9517824.

The previous prime is 28981573. The next prime is 28981591. The reversal of 28981584 is 48518982.

It is a happy number.

It is a super-2 number, since 2×28981584² = 1679864422298112, which contains 22 as substring.

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, 31077 + ... + 31995.

It is an arithmetic number, because the mean of its divisors is an integer number (1055240).

Almost surely, 2^28981584 is an apocalyptic number.

28981584 is a gapful number since it is divisible by the number (24) 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 28981584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42209600).

28981584 is an abundant number, since it is smaller than the sum of its proper divisors (55437616).

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

28981584 is a wasteful number, since it uses less digits than its factorization.

28981584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1009 (or 997 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 28981584 is about 5383.4546529157. The cubic root of 28981584 is about 307.1666345599.

The spelling of 28981584 in words is "twenty-eight million, nine hundred eighty-one thousand, five hundred eighty-four".