28811140 has 12 divisors (see below), whose sum is σ = 60503436. Its totient is φ = 11524448.

The previous prime is 28811137. The next prime is 28811173. The reversal of 28811140 is 4111882.

It can be written as a sum of positive squares in 2 ways, for example, as 18455616 + 10355524 = 4296^2 + 3218^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 720259 + ... + 720298.

It is an arithmetic number, because the mean of its divisors is an integer number (5041953).

Almost surely, 2^28811140 is an apocalyptic number.

28811140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28811140 is an abundant number, since it is smaller than the sum of its proper divisors (31692296).

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

28811140 is a wasteful number, since it uses less digits than its factorization.

28811140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1440566 (or 1440564 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 25.

The square root of 28811140 is about 5367.6009538713. The cubic root of 28811140 is about 306.5632895622.

The spelling of 28811140 in words is "twenty-eight million, eight hundred eleven thousand, one hundred forty".