221161668 has 48 divisors (see below), whose sum is σ = 635134080. Its totient is φ = 58328064.

The previous prime is 221161651. The next prime is 221161693. The reversal of 221161668 is 866161122.

221161668 is digitally balanced in base 3, 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 (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100173 + ... + 102356.

It is an arithmetic number, because the mean of its divisors is an integer number (13231960).

Almost surely, 2^221161668 is an apocalyptic number.

221161668 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

221161668 is an abundant number, since it is smaller than the sum of its proper divisors (413972412).

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

221161668 is a wasteful number, since it uses less digits than its factorization.

221161668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202556 (or 202554 counting only the distinct ones).

The product of its digits is 6912, while the sum is 33.

The square root of 221161668 is about 14871.5052365253. The cubic root of 221161668 is about 604.7417498524.

The spelling of 221161668 in words is "two hundred twenty-one million, one hundred sixty-one thousand, six hundred sixty-eight".