28251520 has 64 divisors (see below), whose sum is σ = 73697040. Its totient is φ = 10270720.

The previous prime is 28251497. The next prime is 28251527. The reversal of 28251520 is 2515282.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28251527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5034 + ... + 9046.

Almost surely, 2^28251520 is an apocalyptic number.

28251520 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 28251520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36848520).

28251520 is an abundant number, since it is smaller than the sum of its proper divisors (45445520).

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

28251520 is a wasteful number, since it uses less digits than its factorization.

28251520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4043 (or 4031 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 28251520 is about 5315.2158940160. The cubic root of 28251520 is about 304.5654296625.

The spelling of 28251520 in words is "twenty-eight million, two hundred fifty-one thousand, five hundred twenty".