28368720 has 180 divisors, whose sum is σ = 100845108. Its totient is φ = 7142400.

The previous prime is 28368719. The next prime is 28368731. The reversal of 28368720 is 2786382.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 4981824 + 23386896 = 2232^2 + 4836^2 .

It is a tau number, because it is divible by the number of its divisors (180).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 691900 + ... + 691940.

Almost surely, 2^28368720 is an apocalyptic number.

28368720 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 28368720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50422554).

28368720 is an abundant number, since it is smaller than the sum of its proper divisors (72476388).

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

28368720 is a wasteful number, since it uses less digits than its factorization.

28368720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 28368720 is about 5326.2294355388. The cubic root of 28368720 is about 304.9860067037.

The spelling of 28368720 in words is "twenty-eight million, three hundred sixty-eight thousand, seven hundred twenty".