28012530 has 128 divisors (see below), whose sum is σ = 85671936. Its totient is φ = 5702400.

The previous prime is 28012529. The next prime is 28012541. The reversal of 28012530 is 3521082.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 28012497 and 28012506.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 84465 + ... + 84795.

It is an arithmetic number, because the mean of its divisors is an integer number (669312).

Almost surely, 2^28012530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28012530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42835968).

28012530 is an abundant number, since it is smaller than the sum of its proper divisors (57659406).

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

28012530 is a wasteful number, since it uses less digits than its factorization.

28012530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 28012530 is about 5292.6864634135. The cubic root of 28012530 is about 303.7041862181.

The spelling of 28012530 in words is "twenty-eight million, twelve thousand, five hundred thirty".