221688868 has 12 divisors (see below), whose sum is σ = 388290672. Its totient is φ = 110748680.

The previous prime is 221688853. The next prime is 221688889. The reversal of 221688868 is 868886122.

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 3 ways as a sum of consecutive naturals, for example, 18598 + ... + 28093.

It is an arithmetic number, because the mean of its divisors is an integer number (32357556).

Almost surely, 2^221688868 is an apocalyptic number.

It is an amenable number.

221688868 is a deficient number, since it is larger than the sum of its proper divisors (166601804).

221688868 is a wasteful number, since it uses less digits than its factorization.

221688868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47882 (or 47880 counting only the distinct ones).

The product of its digits is 589824, while the sum is 49.

The square root of 221688868 is about 14889.2198586763. The cubic root of 221688868 is about 605.2218916066.

The spelling of 221688868 in words is "two hundred twenty-one million, six hundred eighty-eight thousand, eight hundred sixty-eight".