28032138 has 12 divisors (see below), whose sum is σ = 60736338. Its totient is φ = 9344040.

The previous prime is 28032131. The next prime is 28032143. The reversal of 28032138 is 83123082.

It can be written as a sum of positive squares in only one way, i.e., 23882769 + 4149369 = 4887^2 + 2037^2 .

It is not an unprimeable number, because it can be changed into a prime (28032131) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 778653 + ... + 778688.

Almost surely, 2^28032138 is an apocalyptic number.

28032138 is an abundant number, since it is smaller than the sum of its proper divisors (32704200).

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

28032138 is a wasteful number, since it uses less digits than its factorization.

28032138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557349 (or 1557346 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 28032138 is about 5294.5385068011. The cubic root of 28032138 is about 303.7750312146.

It can be divided in two parts, 2803213 and 8, that added together give a cube (2803221 = 141³).

The spelling of 28032138 in words is "twenty-eight million, thirty-two thousand, one hundred thirty-eight".