28805140 has 192 divisors, whose sum is σ = 84672000. Its totient is φ = 8128512.

The previous prime is 28805113. The next prime is 28805171. The reversal of 28805140 is 4150882.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 28805099 and 28805108.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 1516051 + ... + 1516069.

It is an arithmetic number, because the mean of its divisors is an integer number (441000).

Almost surely, 2^28805140 is an apocalyptic number.

28805140 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 28805140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42336000).

28805140 is an abundant number, since it is smaller than the sum of its proper divisors (55866860).

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

28805140 is a wasteful number, since it uses less digits than its factorization.

28805140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 28.

The square root of 28805140 is about 5367.0420158594. The cubic root of 28805140 is about 306.5420071990.

The spelling of 28805140 in words is "twenty-eight million, eight hundred five thousand, one hundred forty".