28021158 has 48 divisors (see below), whose sum is σ = 66779856. Its totient is φ = 8421120.

The previous prime is 28021141. The next prime is 28021171. The reversal of 28021158 is 85112082.

It is a Curzon number.

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 23 ways as a sum of consecutive naturals, for example, 26610 + ... + 27642.

It is an arithmetic number, because the mean of its divisors is an integer number (1391247).

Almost surely, 2^28021158 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28021158, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33389928).

28021158 is an abundant number, since it is smaller than the sum of its proper divisors (38758698).

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

28021158 is a wasteful number, since it uses less digits than its factorization.

28021158 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1189 (or 1186 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 28021158 is about 5293.5014876734. The cubic root of 28021158 is about 303.7353638225.

The spelling of 28021158 in words is "twenty-eight million, twenty-one thousand, one hundred fifty-eight".