28066440 has 64 divisors (see below), whose sum is σ = 87868800. Its totient is φ = 7158272.

The previous prime is 28066433. The next prime is 28066453. The reversal of 28066440 is 4466082.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 28066398 and 28066407.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2325 + ... + 7844.

It is an arithmetic number, because the mean of its divisors is an integer number (1372950).

Almost surely, 2^28066440 is an apocalyptic number.

28066440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28066440 is an abundant number, since it is smaller than the sum of its proper divisors (59802360).

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

28066440 is a wasteful number, since it uses less digits than its factorization.

28066440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10206 (or 10202 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 30.

The square root of 28066440 is about 5297.7768922445. The cubic root of 28066440 is about 303.8988871946.

The spelling of 28066440 in words is "twenty-eight million, sixty-six thousand, four hundred forty".