221800828 has 12 divisors (see below), whose sum is σ = 388258920. Its totient is φ = 110869712.

The previous prime is 221800793. The next prime is 221800841. The reversal of 221800828 is 828008122.

It is a self number, because there is not a number n which added to its sum of digits gives 221800828.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18483 + ... + 28021.

It is an arithmetic number, because the mean of its divisors is an integer number (32354910).

Almost surely, 2^221800828 is an apocalyptic number.

It is an amenable number.

221800828 is a deficient number, since it is larger than the sum of its proper divisors (166458092).

221800828 is a wasteful number, since it uses less digits than its factorization.

221800828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15356 (or 15354 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 31.

The square root of 221800828 is about 14892.9791512645. The cubic root of 221800828 is about 605.3237599589.

The spelling of 221800828 in words is "two hundred twenty-one million, eight hundred thousand, eight hundred twenty-eight".