28013544 has 72 divisors (see below), whose sum is σ = 82181190. Its totient is φ = 8569728.

The previous prime is 28013539. The next prime is 28013561. The reversal of 28013544 is 44531082.

It can be written as a sum of positive squares in 3 ways, for example, as 27688644 + 324900 = 5262^2 + 570^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 161842 + ... + 162014.

Almost surely, 2^28013544 is an apocalyptic number.

28013544 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 28013544, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41090595).

28013544 is an abundant number, since it is smaller than the sum of its proper divisors (54167646).

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

28013544 is a wasteful number, since it uses less digits than its factorization.

28013544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371 (or 191 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 28013544 is about 5292.7822551093. The cubic root of 28013544 is about 303.7078506774.

It can be divided in two parts, 280 and 13544, that added together give a cube (13824 = 24³).

The spelling of 28013544 in words is "twenty-eight million, thirteen thousand, five hundred forty-four".