72221678568 has 128 divisors (see below), whose sum is σ = 216244828800. Its totient is φ = 22201786368.

The previous prime is 72221678549. The next prime is 72221678597. The reversal of 72221678568 is 86587612227.

72221678568 is a `hidden beast` number, since 7 + 2 + 2 + 2 + 1 + 6 + 78 + 568 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3226471 + ... + 3248777.

It is an arithmetic number, because the mean of its divisors is an integer number (1689412725).

Almost surely, 2^72221678568 is an apocalyptic number.

72221678568 is a gapful number since it is divisible by the number (78) 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 72221678568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108122414400).

72221678568 is an abundant number, since it is smaller than the sum of its proper divisors (144023150232).

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

72221678568 is a wasteful number, since it uses less digits than its factorization.

72221678568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23488 (or 23478 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 54.

The spelling of 72221678568 in words is "seventy-two billion, two hundred twenty-one million, six hundred seventy-eight thousand, five hundred sixty-eight".