219728 has 20 divisors (see below), whose sum is σ = 440448. Its totient is φ = 106080.

The previous prime is 219727. The next prime is 219731. The reversal of 219728 is 827912.

It is a happy number.

219728 is an admirable number.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 219728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (219721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 275 + ... + 717.

2²¹⁹⁷²⁸ 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 219728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (220224).

219728 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

219728 is a wasteful number, since it uses less digits than its factorization.

219728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482 (or 476 counting only the distinct ones).

The product of its digits is 2016, while the sum is 29.

The square root of 219728 is about 468.7515333308. The cubic root of 219728 is about 60.3432181302.

Subtracting from 219728 its product of digits (2016), we obtain a palindrome (217712).

It can be divided in two parts, 2197 and 28, that multiplied together give a palindrome (61516).

The spelling of 219728 in words is "two hundred nineteen thousand, seven hundred twenty-eight".