221247816768 has 560 divisors, whose sum is σ = 730298849280. Its totient is φ = 65672985600.

The previous prime is 221247816767. The next prime is 221247816773. The reversal of 221247816768 is 867618742122.

221247816768 is a `hidden beast` number, since 2 + 2 + 1 + 2 + 478 + 167 + 6 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (221247816761) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 816412473 + ... + 816412743.

It is an arithmetic number, because the mean of its divisors is an integer number (1304105088).

Almost surely, 2^221247816768 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 221247816768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (365149424640).

221247816768 is an abundant number, since it is smaller than the sum of its proper divisors (509051032512).

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

221247816768 is a wasteful number, since it uses less digits than its factorization.

221247816768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548 (or 529 counting only the distinct ones).

The product of its digits is 3612672, while the sum is 54.

The spelling of 221247816768 in words is "two hundred twenty-one billion, two hundred forty-seven million, eight hundred sixteen thousand, seven hundred sixty-eight".