28905140 has 96 divisors (see below), whose sum is σ = 70326144. Its totient is φ = 9884160.

The previous prime is 28905133. The next prime is 28905143. The reversal of 28905140 is 4150982.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28905143) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 431387 + ... + 431453.

It is an arithmetic number, because the mean of its divisors is an integer number (732564).

Almost surely, 2^28905140 is an apocalyptic number.

28905140 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 28905140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35163072).

28905140 is an abundant number, since it is smaller than the sum of its proper divisors (41421004).

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

28905140 is a wasteful number, since it uses less digits than its factorization.

28905140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177 (or 175 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 28905140 is about 5376.3500630074. The cubic root of 28905140 is about 306.8963281745.

The spelling of 28905140 in words is "twenty-eight million, nine hundred five thousand, one hundred forty".