28381760 has 84 divisors (see below), whose sum is σ = 74387964. Its totient is φ = 10306560.

The previous prime is 28381757. The next prime is 28381811. The reversal of 28381760 is 6718382.

It can be written as a sum of positive squares in 2 ways, for example, as 20939776 + 7441984 = 4576^2 + 2728^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 28381760.

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, 38354 + ... + 39086.

It is an arithmetic number, because the mean of its divisors is an integer number (885571).

Almost surely, 2^28381760 is an apocalyptic number.

28381760 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 28381760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37193982).

28381760 is an abundant number, since it is smaller than the sum of its proper divisors (46006204).

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

28381760 is a wasteful number, since it uses less digits than its factorization.

28381760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 772 (or 751 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 28381760 is about 5327.4534254182. The cubic root of 28381760 is about 305.0327296239.

The spelling of 28381760 in words is "twenty-eight million, three hundred eighty-one thousand, seven hundred sixty".