28778184 has 48 divisors (see below), whose sum is σ = 78486720. Its totient is φ = 9525600.

The previous prime is 28778171. The next prime is 28778213. The reversal of 28778184 is 48187782.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9549 + ... + 12195.

It is an arithmetic number, because the mean of its divisors is an integer number (1635140).

Almost surely, 2^28778184 is an apocalyptic number.

28778184 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 28778184, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39243360).

28778184 is an abundant number, since it is smaller than the sum of its proper divisors (49708536).

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

28778184 is a wasteful number, since it uses less digits than its factorization.

28778184 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2810 (or 2803 counting only the distinct ones).

The product of its digits is 200704, while the sum is 45.

The square root of 28778184 is about 5364.5301751412. The cubic root of 28778184 is about 306.4463561537.

The spelling of 28778184 in words is "twenty-eight million, seven hundred seventy-eight thousand, one hundred eighty-four".