221386564872 has 180 divisors, whose sum is σ = 668466974175. Its totient is φ = 66141952800.

The previous prime is 221386564859. The next prime is 221386564909. The reversal of 221386564872 is 278465683122.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

221386564872 is a `hidden beast` number, since 2 + 2 + 1 + 3 + 8 + 6 + 564 + 8 + 72 = 666.

221386564872 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 110693282436 + 110693282436 = 332706^2 + 332706^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=332706.

It is a super-2 number, since 2×221386564872² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 3118120597 + ... + 3118120667.

Almost surely, 2^221386564872 is an apocalyptic number.

221386564872 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 221386564872

221386564872 is an abundant number, since it is smaller than the sum of its proper divisors (447080409303).

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

221386564872 is an frugal number, since it uses more digits than its factorization.

221386564872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 318 (or 87 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 54.

The spelling of 221386564872 in words is "two hundred twenty-one billion, three hundred eighty-six million, five hundred sixty-four thousand, eight hundred seventy-two".