28939128 has 32 divisors (see below), whose sum is σ = 76156800. Its totient is φ = 9138528.

The previous prime is 28939123. The next prime is 28939133. The reversal of 28939128 is 82193982.

It is an interprime number because it is at equal distance from previous prime (28939123) and next prime (28939133).

It is a self number, because there is not a number n which added to its sum of digits gives 28939128.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28939121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31276 + ... + 32187.

It is an arithmetic number, because the mean of its divisors is an integer number (2379900).

Almost surely, 2^28939128 is an apocalyptic number.

It is an amenable number.

28939128 is an abundant number, since it is smaller than the sum of its proper divisors (47217672).

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

28939128 is a wasteful number, since it uses less digits than its factorization.

28939128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63491 (or 63487 counting only the distinct ones).

The product of its digits is 62208, while the sum is 42.

The square root of 28939128 is about 5379.5100148619. The cubic root of 28939128 is about 307.0165686892.

It can be divided in two parts, 2893 and 9128, that added together give a palindrome (12021).

The spelling of 28939128 in words is "twenty-eight million, nine hundred thirty-nine thousand, one hundred twenty-eight".