28542720 has 72 divisors (see below), whose sum is σ = 91170576. Its totient is φ = 7610368.

The previous prime is 28542713. The next prime is 28542727. The reversal of 28542720 is 2724582.

It is an interprime number because it is at equal distance from previous prime (28542713) and next prime (28542727).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28542727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124 + ... + 7556.

It is an arithmetic number, because the mean of its divisors is an integer number (1266258).

Almost surely, 2^28542720 is an apocalyptic number.

28542720 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 28542720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45585288).

28542720 is an abundant number, since it is smaller than the sum of its proper divisors (62627856).

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

28542720 is an equidigital number, since it uses as much as digits as its factorization.

28542720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7457 (or 7443 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 30.

The square root of 28542720 is about 5342.5387223679. The cubic root of 28542720 is about 305.6082817123.

The spelling of 28542720 in words is "twenty-eight million, five hundred forty-two thousand, seven hundred twenty".