216655939920 has 320 divisors, whose sum is σ = 807077629440. Its totient is φ = 47029248000.

The previous prime is 216655939889. The next prime is 216655939931. The reversal of 216655939920 is 29939556612.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2935470 + ... + 3008370.

It is an arithmetic number, because the mean of its divisors is an integer number (2522117592).

Almost surely, 2^216655939920 is an apocalyptic number.

216655939920 is a gapful number since it is divisible by the number (20) 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 216655939920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (403538814720).

216655939920 is an abundant number, since it is smaller than the sum of its proper divisors (590421689520).

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

216655939920 is a wasteful number, since it uses less digits than its factorization.

216655939920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73014 (or 73008 counting only the distinct ones).

The product of its (nonzero) digits is 7873200, while the sum is 57.

The spelling of 216655939920 in words is "two hundred sixteen billion, six hundred fifty-five million, nine hundred thirty-nine thousand, nine hundred twenty".