28538928 has 120 divisors (see below), whose sum is σ = 89369280. Its totient is φ = 8426880.

The previous prime is 28538927. The next prime is 28538959. The reversal of 28538928 is 82983582.

28538928 is a `hidden beast` number, since 28 + 538 + 92 + 8 = 666.

It is a super-2 number, since 2×28538928² = 1628940822778368, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28538921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 67903 + ... + 68321.

It is an arithmetic number, because the mean of its divisors is an integer number (744744).

Almost surely, 2^28538928 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28538928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44684640).

28538928 is an abundant number, since it is smaller than the sum of its proper divisors (60830352).

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

28538928 is a wasteful number, since it uses less digits than its factorization.

28538928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487 (or 478 counting only the distinct ones).

The product of its digits is 276480, while the sum is 45.

The square root of 28538928 is about 5342.1838231195. The cubic root of 28538928 is about 305.5947474038.

It can be divided in two parts, 2853 and 8928, that added together give a triangular number (11781 = T₁₅₃).

The spelling of 28538928 in words is "twenty-eight million, five hundred thirty-eight thousand, nine hundred twenty-eight".