218569728 has 132 divisors (see below), whose sum is σ = 632326488. Its totient is φ = 67092480.

The previous prime is 218569717. The next prime is 218569733. The reversal of 218569728 is 827965812.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 518958 + ... + 519378.

Almost surely, 2^218569728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218569728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (316163244).

218569728 is an abundant number, since it is smaller than the sum of its proper divisors (413756760).

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

218569728 is a wasteful number, since it uses less digits than its factorization.

218569728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 470 (or 439 counting only the distinct ones).

The product of its digits is 483840, while the sum is 48.

The square root of 218569728 is about 14784.1038957388. The cubic root of 218569728 is about 602.3700039208.

The spelling of 218569728 in words is "two hundred eighteen million, five hundred sixty-nine thousand, seven hundred twenty-eight".