221297776128 has 480 divisors, whose sum is σ = 755206163712. Its totient is φ = 61500211200.

The previous prime is 221297776111. The next prime is 221297776169. The reversal of 221297776128 is 821677792122.

221297776128 is a `hidden beast` number, since 2 + 2 + 12 + 9 + 7 + 7 + 7 + 612 + 8 = 666.

221297776128 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 110042643 + ... + 110044653.

Almost surely, 2^221297776128 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 221297776128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (377603081856).

221297776128 is an abundant number, since it is smaller than the sum of its proper divisors (533908387584).

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

221297776128 is a wasteful number, since it uses less digits than its factorization.

221297776128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2226 (or 2207 counting only the distinct ones).

The product of its digits is 2370816, while the sum is 54.

The spelling of 221297776128 in words is "two hundred twenty-one billion, two hundred ninety-seven million, seven hundred seventy-six thousand, one hundred twenty-eight".