28072580 has 36 divisors (see below), whose sum is σ = 61091940. Its totient is φ = 10835328.

The previous prime is 28072573. The next prime is 28072589. The reversal of 28072580 is 8527082.

It can be written as a sum of positive squares in 6 ways, for example, as 24964 + 28047616 = 158^2 + 5296^2 .

It is not an unprimeable number, because it can be changed into a prime (28072589) 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 11 ways as a sum of consecutive naturals, for example, 15986 + ... + 17654.

Almost surely, 2^28072580 is an apocalyptic number.

28072580 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 28072580, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30545970).

28072580 is an abundant number, since it is smaller than the sum of its proper divisors (33019360).

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

28072580 is a wasteful number, since it uses less digits than its factorization.

28072580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736 (or 1705 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 32.

The square root of 28072580 is about 5298.3563489067. The cubic root of 28072580 is about 303.9210465555.

The spelling of 28072580 in words is "twenty-eight million, seventy-two thousand, five hundred eighty".