28128548 has 18 divisors (see below), whose sum is σ = 57262086. Its totient is φ = 12055008.

The previous prime is 28128533. The next prime is 28128553. The reversal of 28128548 is 84582182.

It can be written as a sum of positive squares in only one way, i.e., 23600164 + 4528384 = 4858^2 + 2128^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 71561 + ... + 71952.

It is an arithmetic number, because the mean of its divisors is an integer number (3181227).

Almost surely, 2^28128548 is an apocalyptic number.

28128548 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

28128548 is an abundant number, since it is smaller than the sum of its proper divisors (29133538).

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

28128548 is a wasteful number, since it uses less digits than its factorization.

28128548 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143531 (or 143522 counting only the distinct ones).

The product of its digits is 40960, while the sum is 38.

The square root of 28128548 is about 5303.6353569981. The cubic root of 28128548 is about 304.1228871833.

The spelling of 28128548 in words is "twenty-eight million, one hundred twenty-eight thousand, five hundred forty-eight".