28385218 has 8 divisors (see below), whose sum is σ = 42614460. Its totient is φ = 14180400.

The previous prime is 28385209. The next prime is 28385219. The reversal of 28385218 is 81258382.

It can be written as a sum of positive squares in 2 ways, for example, as 21557449 + 6827769 = 4643^2 + 2613^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (28385219) by changing a digit.

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, 2853 + ... + 8056.

Almost surely, 2^28385218 is an apocalyptic number.

28385218 is a deficient number, since it is larger than the sum of its proper divisors (14229242).

28385218 is a wasteful number, since it uses less digits than its factorization.

28385218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12212.

The product of its digits is 30720, while the sum is 37.

The square root of 28385218 is about 5327.7779608388. Note that the first 3 decimals coincide. The cubic root of 28385218 is about 305.0451173962.

The spelling of 28385218 in words is "twenty-eight million, three hundred eighty-five thousand, two hundred eighteen".