221520328 has 16 divisors (see below), whose sum is σ = 429673500. Its totient is φ = 106940736.

The previous prime is 221520317. The next prime is 221520347. The reversal of 221520328 is 823025122.

It can be written as a sum of positive squares in 2 ways, for example, as 200562244 + 20958084 = 14162^2 + 4578^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 477183 + ... + 477646.

Almost surely, 2^221520328 is an apocalyptic number.

It is an amenable number.

221520328 is a deficient number, since it is larger than the sum of its proper divisors (208153172).

221520328 is a wasteful number, since it uses less digits than its factorization.

221520328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954864 (or 954860 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 221520328 is about 14883.5589829852. The cubic root of 221520328 is about 605.0684784633.

The spelling of 221520328 in words is "two hundred twenty-one million, five hundred twenty thousand, three hundred twenty-eight".