28105530 has 64 divisors (see below), whose sum is σ = 71221248. Its totient is φ = 7087680.

The previous prime is 28105513. The next prime is 28105547. The reversal of 28105530 is 3550182.

It is an interprime number because it is at equal distance from previous prime (28105513) and next prime (28105547).

It is a self number, because there is not a number n which added to its sum of digits gives 28105530.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 43389 + ... + 44031.

It is an arithmetic number, because the mean of its divisors is an integer number (1112832).

Almost surely, 2^28105530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28105530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35610624).

28105530 is an abundant number, since it is smaller than the sum of its proper divisors (43115718).

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

28105530 is a wasteful number, since it uses less digits than its factorization.

28105530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 731.

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 28105530 is about 5301.4648918954. The cubic root of 28105530 is about 304.0399084841.

The spelling of 28105530 in words is "twenty-eight million, one hundred five thousand, five hundred thirty".