28821144 has 32 divisors (see below), whose sum is σ = 78603840. Its totient is φ = 8733600.

The previous prime is 28821131. The next prime is 28821161. The reversal of 28821144 is 44112882.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54322 + ... + 54849.

It is an arithmetic number, because the mean of its divisors is an integer number (2456370).

Almost surely, 2^28821144 is an apocalyptic number.

28821144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28821144 is an abundant number, since it is smaller than the sum of its proper divisors (49782696).

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

28821144 is a wasteful number, since it uses less digits than its factorization.

28821144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109191 (or 109187 counting only the distinct ones).

The product of its digits is 4096, while the sum is 30.

The square root of 28821144 is about 5368.5327604477. The cubic root of 28821144 is about 306.5987677864.

The spelling of 28821144 in words is "twenty-eight million, eight hundred twenty-one thousand, one hundred forty-four".