221615751168 has 684 divisors, whose sum is σ = 783209280672. Its totient is φ = 62426972160.

The previous prime is 221615751163. The next prime is 221615751251. The reversal of 221615751168 is 861157516122.

221615751168 is a `hidden beast` number, since 2 + 2 + 1 + 6 + 1 + 575 + 11 + 68 = 666.

It is a super-2 number, since 2×221615751168² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221615751163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3121348573 + ... + 3121348643.

It is an arithmetic number, because the mean of its divisors is an integer number (1145042808).

Almost surely, 2^221615751168 is an apocalyptic number.

221615751168 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 221615751168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (391604640336).

221615751168 is an abundant number, since it is smaller than the sum of its proper divisors (561593529504).

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

221615751168 is an frugal number, since it uses more digits than its factorization.

221615751168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136 (or 83 counting only the distinct ones).

The product of its digits is 201600, while the sum is 45.

The spelling of 221615751168 in words is "two hundred twenty-one billion, six hundred fifteen million, seven hundred fifty-one thousand, one hundred sixty-eight".