218419728 has 20 divisors (see below), whose sum is σ = 564251088. Its totient is φ = 72806560.

The previous prime is 218419717. The next prime is 218419739. The reversal of 218419728 is 827914812.

It is an interprime number because it is at equal distance from previous prime (218419717) and next prime (218419739).

It is a self number, because there is not a number n which added to its sum of digits gives 218419728.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2275158 + ... + 2275253.

Almost surely, 2^218419728 is an apocalyptic number.

It is an amenable number.

218419728 is an abundant number, since it is smaller than the sum of its proper divisors (345831360).

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

218419728 is a wasteful number, since it uses less digits than its factorization.

218419728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4550422 (or 4550416 counting only the distinct ones).

The product of its digits is 64512, while the sum is 42.

The square root of 218419728 is about 14779.0300087658. The cubic root of 218419728 is about 602.2321742542.

It can be divided in two parts, 2184 and 19728, that added together give a palindrome (21912).

The spelling of 218419728 in words is "two hundred eighteen million, four hundred nineteen thousand, seven hundred twenty-eight".