221214921856 has 64 divisors (see below), whose sum is σ = 464747292000. Its totient is φ = 104593821696.

The previous prime is 221214921853. The next prime is 221214921877. The reversal of 221214921856 is 658129412122.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (221214921853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1247160 + ... + 1413448.

Almost surely, 2^221214921856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221214921856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232373646000).

221214921856 is an abundant number, since it is smaller than the sum of its proper divisors (243532370144).

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

221214921856 is a wasteful number, since it uses less digits than its factorization.

221214921856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166869 (or 166857 counting only the distinct ones).

The product of its digits is 138240, while the sum is 43.

The spelling of 221214921856 in words is "two hundred twenty-one billion, two hundred fourteen million, nine hundred twenty-one thousand, eight hundred fifty-six".