28021248 has 80 divisors (see below), whose sum is σ = 82985760. Its totient is φ = 9335808.

The previous prime is 28021237. The next prime is 28021249. The reversal of 28021248 is 84212082.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (28021249) 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, 12811 + ... + 14837.

It is an arithmetic number, because the mean of its divisors is an integer number (1037322).

Almost surely, 2^28021248 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28021248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41492880).

28021248 is an abundant number, since it is smaller than the sum of its proper divisors (54964512).

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

28021248 is an equidigital number, since it uses as much as digits as its factorization.

28021248 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2054 (or 2032 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 28021248 is about 5293.5099886559. The cubic root of 28021248 is about 303.7356890072.

It can be divided in two parts, 280 and 21248, that added together give a triangular number (21528 = T₂₀₇).

The spelling of 28021248 in words is "twenty-eight million, twenty-one thousand, two hundred forty-eight".