216805562880 has 80 divisors (see below), whose sum is σ = 693100308384. Its totient is φ = 57814814720.

The previous prime is 216805562879. The next prime is 216805562887. The reversal of 216805562880 is 88265508612.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (216805562887) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 14107266 + ... + 14122625.

Almost surely, 2^216805562880 is an apocalyptic number.

216805562880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216805562880 is an abundant number, since it is smaller than the sum of its proper divisors (476294745504).

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

216805562880 is an equidigital number, since it uses as much as digits as its factorization.

216805562880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28229917 (or 28229901 counting only the distinct ones).

The product of its (nonzero) digits is 1843200, while the sum is 51.

The spelling of 216805562880 in words is "two hundred sixteen billion, eight hundred five million, five hundred sixty-two thousand, eight hundred eighty".