28191144 has 64 divisors (see below), whose sum is σ = 73497600. Its totient is φ = 9003456.

The previous prime is 28191139. The next prime is 28191167. The reversal of 28191144 is 44119182.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60657 + ... + 61119.

It is an arithmetic number, because the mean of its divisors is an integer number (1148400).

Almost surely, 2^28191144 is an apocalyptic number.

28191144 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 28191144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36748800).

28191144 is an abundant number, since it is smaller than the sum of its proper divisors (45306456).

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

28191144 is a wasteful number, since it uses less digits than its factorization.

28191144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 574 (or 570 counting only the distinct ones).

The product of its digits is 2304, while the sum is 30.

The square root of 28191144 is about 5309.5333128251. The cubic root of 28191144 is about 304.3483138259.

It can be divided in two parts, 28191 and 144, that multiplied together give a palindrome (4059504).

The spelling of 28191144 in words is "twenty-eight million, one hundred ninety-one thousand, one hundred forty-four".