28540040 has 16 divisors (see below), whose sum is σ = 64215180. Its totient is φ = 11416000.

The previous prime is 28540027. The next prime is 28540051. The reversal of 28540040 is 4004582.

It can be written as a sum of positive squares in 2 ways, for example, as 28494244 + 45796 = 5338^2 + 214^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28539988 and 28540015.

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 3 ways as a sum of consecutive naturals, for example, 356711 + ... + 356790.

Almost surely, 2^28540040 is an apocalyptic number.

28540040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28540040 is an abundant number, since it is smaller than the sum of its proper divisors (35675140).

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

28540040 is a wasteful number, since it uses less digits than its factorization.

28540040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 713512 (or 713508 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 23.

The square root of 28540040 is about 5342.2878993929. The cubic root of 28540040 is about 305.5987164498.

The spelling of 28540040 in words is "twenty-eight million, five hundred forty thousand, forty".