216779381568 has 56 divisors (see below), whose sum is σ = 637291242560. Its totient is φ = 72259793280.

The previous prime is 216779381561. The next prime is 216779381629. The reversal of 216779381568 is 865183977612.

216779381568 is a `hidden beast` number, since 2 + 1 + 67 + 7 + 9 + 3 + 8 + 1 + 568 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216779381561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 62723788 + ... + 62727243.

It is an arithmetic number, because the mean of its divisors is an integer number (11380200760).

Almost surely, 2^216779381568 is an apocalyptic number.

It is an amenable number.

216779381568 is an abundant number, since it is smaller than the sum of its proper divisors (420511860992).

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

216779381568 is a wasteful number, since it uses less digits than its factorization.

216779381568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125451052 (or 125451036 counting only the distinct ones).

The product of its digits is 30481920, while the sum is 63.

The spelling of 216779381568 in words is "two hundred sixteen billion, seven hundred seventy-nine million, three hundred eighty-one thousand, five hundred sixty-eight".