28911040 has 56 divisors (see below), whose sum is σ = 69384672. Its totient is φ = 11473920.

The previous prime is 28911037. The next prime is 28911041. The reversal of 28911040 is 4011982.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 28910996 and 28911014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28911041) 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 7 ways as a sum of consecutive naturals, for example, 53170 + ... + 53710.

It is an arithmetic number, because the mean of its divisors is an integer number (1239012).

Almost surely, 2^28911040 is an apocalyptic number.

28911040 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 28911040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34692336).

28911040 is an abundant number, since it is smaller than the sum of its proper divisors (40473632).

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

28911040 is a wasteful number, since it uses less digits than its factorization.

28911040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 725 (or 715 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 28911040 is about 5376.8987344007. The cubic root of 28911040 is about 306.9172075654.

The spelling of 28911040 in words is "twenty-eight million, nine hundred eleven thousand, forty".