221528944 has 80 divisors (see below), whose sum is σ = 531340992. Its totient is φ = 87128064.

The previous prime is 221528927. The next prime is 221528947. The reversal of 221528944 is 449825122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221528947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 338922 + ... + 339574.

Almost surely, 2^221528944 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 221528944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265670496).

221528944 is an abundant number, since it is smaller than the sum of its proper divisors (309812048).

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

221528944 is a wasteful number, since it uses less digits than its factorization.

221528944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 914 (or 908 counting only the distinct ones).

The product of its digits is 46080, while the sum is 37.

The square root of 221528944 is about 14883.8484270702. The cubic root of 221528944 is about 605.0763230442.

The spelling of 221528944 in words is "two hundred twenty-one million, five hundred twenty-eight thousand, nine hundred forty-four".