28945638 has 48 divisors (see below), whose sum is σ = 66044160. Its totient is φ = 9144432.

The previous prime is 28945621. The next prime is 28945639. The reversal of 28945638 is 83654982.

28945638 is a `hidden beast` number, since 2 + 8 + 9 + 4 + 5 + 638 = 666.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28945593 and 28945602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28945639) 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, 57295 + ... + 57797.

It is an arithmetic number, because the mean of its divisors is an integer number (1375920).

Almost surely, 2^28945638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28945638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33022080).

28945638 is an abundant number, since it is smaller than the sum of its proper divisors (37098522).

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

28945638 is a wasteful number, since it uses less digits than its factorization.

28945638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673 (or 670 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 28945638 is about 5380.1150545318. The cubic root of 28945638 is about 307.0395885951.

The spelling of 28945638 in words is "twenty-eight million, nine hundred forty-five thousand, six hundred thirty-eight".