28989738 has 40 divisors (see below), whose sum is σ = 65448900. Its totient is φ = 9590400.

The previous prime is 28989731. The next prime is 28989757. The reversal of 28989738 is 83798982.

It can be written as a sum of positive squares in 2 ways, for example, as 20007729 + 8982009 = 4473^2 + 2997^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (28989731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 23538 + ... + 24738.

Almost surely, 2^28989738 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28989738, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32724450).

28989738 is an abundant number, since it is smaller than the sum of its proper divisors (36459162).

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

28989738 is a wasteful number, since it uses less digits than its factorization.

28989738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1364 (or 1355 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 54.

The square root of 28989738 is about 5384.2119200492. The cubic root of 28989738 is about 307.1954390802.

The spelling of 28989738 in words is "twenty-eight million, nine hundred eighty-nine thousand, seven hundred thirty-eight".