28038920 has 64 divisors (see below), whose sum is σ = 77656320. Its totient is φ = 8872704.

The previous prime is 28038893. The next prime is 28038929. The reversal of 28038920 is 2983082.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (28038929) 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 15 ways as a sum of consecutive naturals, for example, 212 + ... + 7491.

It is an arithmetic number, because the mean of its divisors is an integer number (1213380).

Almost surely, 2^28038920 is an apocalyptic number.

28038920 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 28038920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38828160).

28038920 is an abundant number, since it is smaller than the sum of its proper divisors (49617400).

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

28038920 is a wasteful number, since it uses less digits than its factorization.

28038920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7734 (or 7730 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 28038920 is about 5295.1789393749. The cubic root of 28038920 is about 303.7995273381.

The spelling of 28038920 in words is "twenty-eight million, thirty-eight thousand, nine hundred twenty".