220321728 has 224 divisors, whose sum is σ = 721278720. Its totient is φ = 65387520.

The previous prime is 220321697. The next prime is 220321781. The reversal of 220321728 is 827123022.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 1273450 + ... + 1273622.

Almost surely, 2^220321728 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 220321728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360639360).

220321728 is an abundant number, since it is smaller than the sum of its proper divisors (500956992).

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

220321728 is a wasteful number, since it uses less digits than its factorization.

220321728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272 (or 256 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 220321728 is about 14843.2384606595. The cubic root of 220321728 is about 603.9752047480.

The spelling of 220321728 in words is "two hundred twenty million, three hundred twenty-one thousand, seven hundred twenty-eight".