28021488 has 80 divisors (see below), whose sum is σ = 80161536. Its totient is φ = 8363520.

The previous prime is 28021421. The next prime is 28021501. The reversal of 28021488 is 88412082.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (33).

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 15 ways as a sum of consecutive naturals, for example, 38181 + ... + 38907.

Almost surely, 2^28021488 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 28021488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40080768).

28021488 is an abundant number, since it is smaller than the sum of its proper divisors (52140048).

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

28021488 is a wasteful number, since it uses less digits than its factorization.

28021488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822 (or 816 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 33.

The square root of 28021488 is about 5293.5326578760. The cubic root of 28021488 is about 303.7365561629.

The spelling of 28021488 in words is "twenty-eight million, twenty-one thousand, four hundred eighty-eight".