28440018 has 16 divisors (see below), whose sum is σ = 63200160. Its totient is φ = 9479988.

The previous prime is 28440007. The next prime is 28440037. The reversal of 28440018 is 81004482.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28439973 and 28440000.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 263280 + ... + 263387.

It is an arithmetic number, because the mean of its divisors is an integer number (3950010).

Almost surely, 2^28440018 is an apocalyptic number.

28440018 is an abundant number, since it is smaller than the sum of its proper divisors (34760142).

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

28440018 is a wasteful number, since it uses less digits than its factorization.

28440018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526678 (or 526672 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 28440018 is about 5332.9183380209. The cubic root of 28440018 is about 305.2412961074.

The spelling of 28440018 in words is "twenty-eight million, four hundred forty thousand, eighteen".