221428930 has 32 divisors (see below), whose sum is σ = 409147200. Its totient is φ = 86235072.

The previous prime is 221428913. The next prime is 221428997. The reversal of 221428930 is 39824122.

221428930 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 221428892 and 221428901.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 179556 + ... + 180784.

It is an arithmetic number, because the mean of its divisors is an integer number (12785850).

Almost surely, 2^221428930 is an apocalyptic number.

221428930 is a deficient number, since it is larger than the sum of its proper divisors (187718270).

221428930 is a wasteful number, since it uses less digits than its factorization.

221428930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698.

The product of its (nonzero) digits is 6912, while the sum is 31.

The square root of 221428930 is about 14880.4882312376. The cubic root of 221428930 is about 604.9852511032.

The spelling of 221428930 in words is "two hundred twenty-one million, four hundred twenty-eight thousand, nine hundred thirty".