28520550 has 72 divisors (see below), whose sum is σ = 77956320. Its totient is φ = 7473600.

The previous prime is 28520521. The next prime is 28520551. The reversal of 28520550 is 5502582.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28520551) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 26931 + ... + 27969.

Almost surely, 2^28520550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28520550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38978160).

28520550 is an abundant number, since it is smaller than the sum of its proper divisors (49435770).

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

28520550 is a wasteful number, since it uses less digits than its factorization.

28520550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1118 (or 1110 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 27.

The square root of 28520550 is about 5340.4634630339. The cubic root of 28520550 is about 305.5291361302.

The spelling of 28520550 in words is "twenty-eight million, five hundred twenty thousand, five hundred fifty".