28006520 has 32 divisors (see below), whose sum is σ = 63730800. Its totient is φ = 11075328.

The previous prime is 28006507. The next prime is 28006543. The reversal of 28006520 is 2560082.

It is a happy 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 7 ways as a sum of consecutive naturals, for example, 374 + ... + 7493.

Almost surely, 2^28006520 is an apocalyptic number.

28006520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28006520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31865400).

28006520 is an abundant number, since it is smaller than the sum of its proper divisors (35724280).

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

28006520 is a wasteful number, since it uses less digits than its factorization.

28006520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7967 (or 7963 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 28006520 is about 5292.1186683596. The cubic root of 28006520 is about 303.6824650727.

The spelling of 28006520 in words is "twenty-eight million, six thousand, five hundred twenty".