221323216128 has 288 divisors, whose sum is σ = 701747257344. Its totient is φ = 60604194816.

The previous prime is 221323216117. The next prime is 221323216129. The reversal of 221323216128 is 821612323122.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221323216129) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 13318801 + ... + 13335407.

Almost surely, 2^221323216128 is an apocalyptic number.

221323216128 is a gapful number since it is divisible by the number (28) 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 221323216128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (350873628672).

221323216128 is an abundant number, since it is smaller than the sum of its proper divisors (480424041216).

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

221323216128 is a wasteful number, since it uses less digits than its factorization.

221323216128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16737 (or 16723 counting only the distinct ones).

The product of its digits is 13824, while the sum is 33.

The spelling of 221323216128 in words is "two hundred twenty-one billion, three hundred twenty-three million, two hundred sixteen thousand, one hundred twenty-eight".