28781448 has 48 divisors (see below), whose sum is σ = 74070480. Its totient is φ = 9314592.

The previous prime is 28781429. The next prime is 28781453. The reversal of 28781448 is 84418782.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 172261 + ... + 172427.

It is an arithmetic number, because the mean of its divisors is an integer number (1543135).

Almost surely, 2^28781448 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28781448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37035240).

28781448 is an abundant number, since it is smaller than the sum of its proper divisors (45289032).

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

28781448 is a wasteful number, since it uses less digits than its factorization.

28781448 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386 (or 215 counting only the distinct ones).

The product of its digits is 114688, while the sum is 42.

The square root of 28781448 is about 5364.8343870058. The cubic root of 28781448 is about 306.4579413542.

The spelling of 28781448 in words is "twenty-eight million, seven hundred eighty-one thousand, four hundred forty-eight".