28422720 has 168 divisors, whose sum is σ = 99852480. Its totient is φ = 7418880.

The previous prime is 28422707. The next prime is 28422721. The reversal of 28422720 is 2722482.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28422721) 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, 204411 + ... + 204549.

It is an arithmetic number, because the mean of its divisors is an integer number (594360).

Almost surely, 2^28422720 is an apocalyptic number.

28422720 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 28422720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49926240).

28422720 is an abundant number, since it is smaller than the sum of its proper divisors (71429760).

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

28422720 is a wasteful number, since it uses less digits than its factorization.

28422720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233 (or 220 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 28422720 is about 5331.2962776421. The cubic root of 28422720 is about 305.1793981766.

The spelling of 28422720 in words is "twenty-eight million, four hundred twenty-two thousand, seven hundred twenty".