216600660 has 144 divisors (see below), whose sum is σ = 693149184. Its totient is φ = 54641664.

The previous prime is 216600653. The next prime is 216600677. The reversal of 216600660 is 66006612.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 467589 + ... + 468051.

It is an arithmetic number, because the mean of its divisors is an integer number (4813536).

Almost surely, 2^216600660 is an apocalyptic number.

216600660 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 216600660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (346574592).

216600660 is an abundant number, since it is smaller than the sum of its proper divisors (476548524).

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

216600660 is a wasteful number, since it uses less digits than its factorization.

216600660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614 (or 609 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 216600660 is about 14717.3591381063. The cubic root of 216600660 is about 600.5556519260. Note that the first 3 decimals are identical.

The spelling of 216600660 in words is "two hundred sixteen million, six hundred thousand, six hundred sixty".