221829728 has 12 divisors (see below), whose sum is σ = 436727340. Its totient is φ = 110914848.

The previous prime is 221829703. The next prime is 221829737. The reversal of 221829728 is 827928122.

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 as a sum of consecutive naturals, namely, 3466058 + ... + 3466121.

It is an arithmetic number, because the mean of its divisors is an integer number (36393945).

Almost surely, 2^221829728 is an apocalyptic number.

It is an amenable number.

221829728 is a deficient number, since it is larger than the sum of its proper divisors (214897612).

221829728 is an equidigital number, since it uses as much as digits as its factorization.

221829728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6932189 (or 6932181 counting only the distinct ones).

The product of its digits is 64512, while the sum is 41.

The square root of 221829728 is about 14893.9493755014. The cubic root of 221829728 is about 605.3500494563.

The spelling of 221829728 in words is "two hundred twenty-one million, eight hundred twenty-nine thousand, seven hundred twenty-eight".