222628728 has 64 divisors (see below), whose sum is σ = 638277120. Its totient is φ = 63388800.

The previous prime is 222628723. The next prime is 222628751. The reversal of 222628728 is 827826222.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (222628723) 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 15 ways as a sum of consecutive naturals, for example, 50118 + ... + 54378.

It is an arithmetic number, because the mean of its divisors is an integer number (9973080).

Almost surely, 2^222628728 is an apocalyptic number.

222628728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 222628728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (319138560).

222628728 is an abundant number, since it is smaller than the sum of its proper divisors (415648392).

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

222628728 is a wasteful number, since it uses less digits than its factorization.

222628728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4588 (or 4584 counting only the distinct ones).

The product of its digits is 86016, while the sum is 39.

The square root of 222628728 is about 14920.7482386106. The cubic root of 222628728 is about 606.0759743107.

The spelling of 222628728 in words is "two hundred twenty-two million, six hundred twenty-eight thousand, seven hundred twenty-eight".