221666557200 has 480 divisors, whose sum is σ = 810243855360. Its totient is φ = 51277670400.

The previous prime is 221666557171. The next prime is 221666557219. The reversal of 221666557200 is 2755666122.

221666557200 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 207358266 + ... + 207359334.

It is an arithmetic number, because the mean of its divisors is an integer number (1688008032).

Almost surely, 2^221666557200 is an apocalyptic number.

221666557200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221666557200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (405121927680).

221666557200 is an abundant number, since it is smaller than the sum of its proper divisors (588577298160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221666557200 is a wasteful number, since it uses less digits than its factorization.

221666557200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1807 (or 1796 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 42.

The spelling of 221666557200 in words is "two hundred twenty-one billion, six hundred sixty-six million, five hundred fifty-seven thousand, two hundred".