28591056 has 100 divisors (see below), whose sum is σ = 89168772. Its totient is φ = 8792064.

The previous prime is 28591051. The next prime is 28591081. The reversal of 28591056 is 65019582.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17139600 + 11451456 = 4140^2 + 3384^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 28591056.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28591051) 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 19 ways as a sum of consecutive naturals, for example, 16000 + ... + 17696.

Almost surely, 2^28591056 is an apocalyptic number.

28591056 is a gapful number since it is divisible by the number (26) 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 28591056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44584386).

28591056 is an abundant number, since it is smaller than the sum of its proper divisors (60577716).

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

28591056 is a wasteful number, since it uses less digits than its factorization.

28591056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1730 (or 1715 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 28591056 is about 5347.0605008734. The cubic root of 28591056 is about 305.7806963852.

The spelling of 28591056 in words is "twenty-eight million, five hundred ninety-one thousand, fifty-six".