28839720 has 256 divisors, whose sum is σ = 112896000. Its totient is φ = 5723136.

The previous prime is 28839689. The next prime is 28839721. The reversal of 28839720 is 2793882.

It is a super-3 number, since 3×28839720³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (28839721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 207411 + ... + 207549.

It is an arithmetic number, because the mean of its divisors is an integer number (441000).

Almost surely, 2^28839720 is an apocalyptic number.

28839720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28839720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56448000).

28839720 is an abundant number, since it is smaller than the sum of its proper divisors (84056280).

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

28839720 is a wasteful number, since it uses less digits than its factorization.

28839720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192 (or 188 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 39.

The square root of 28839720 is about 5370.2625634135. The cubic root of 28839720 is about 306.6646240150.

The spelling of 28839720 in words is "twenty-eight million, eight hundred thirty-nine thousand, seven hundred twenty".