28125990 has 96 divisors (see below), whose sum is σ = 80061696. Its totient is φ = 6819840.

The previous prime is 28125989. The next prime is 28126003. The reversal of 28125990 is 9952182.

It is a Curzon 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 47 ways as a sum of consecutive naturals, for example, 47134 + ... + 47726.

It is an arithmetic number, because the mean of its divisors is an integer number (833976).

Almost surely, 2^28125990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28125990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40030848).

28125990 is an abundant number, since it is smaller than the sum of its proper divisors (51935706).

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

28125990 is a wasteful number, since it uses less digits than its factorization.

28125990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654 (or 651 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 28125990 is about 5303.3941961729. The cubic root of 28125990 is about 304.1136679620.

The spelling of 28125990 in words is "twenty-eight million, one hundred twenty-five thousand, nine hundred ninety".