221655556672 has 112 divisors (see below), whose sum is σ = 486012524544. Its totient is φ = 99461120000.

The previous prime is 221655556663. The next prime is 221655556693. The reversal of 221655556672 is 276655556122.

221655556672 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 polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25095297 + ... + 25104127.

Almost surely, 2^221655556672 is an apocalyptic number.

221655556672 is a gapful number since it is divisible by the number (22) 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 221655556672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (243006262272).

221655556672 is an abundant number, since it is smaller than the sum of its proper divisors (264356967872).

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

221655556672 is a wasteful number, since it uses less digits than its factorization.

221655556672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9308 (or 9298 counting only the distinct ones).

The product of its digits is 7560000, while the sum is 52.

The spelling of 221655556672 in words is "two hundred twenty-one billion, six hundred fifty-five million, five hundred fifty-six thousand, six hundred seventy-two".