217422216 has 96 divisors (see below), whose sum is σ = 645390720. Its totient is φ = 65577600.

The previous prime is 217422203. The next prime is 217422217. The reversal of 217422216 is 612224712.

217422216 is a `hidden beast` number, since 21 + 7 + 422 + 216 = 666.

217422216 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 217422216.

It is not an unprimeable number, because it can be changed into a prime (217422217) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 214126 + ... + 215138.

It is an arithmetic number, because the mean of its divisors is an integer number (6722820).

Almost surely, 2^217422216 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217422216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322695360).

217422216 is an abundant number, since it is smaller than the sum of its proper divisors (427968504).

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

217422216 is a wasteful number, since it uses less digits than its factorization.

217422216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1307 (or 1300 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 217422216 is about 14745.2438433550. The cubic root of 217422216 is about 601.3139869631.

Adding to 217422216 its reverse (612224712), we get a palindrome (829646928).

The spelling of 217422216 in words is "two hundred seventeen million, four hundred twenty-two thousand, two hundred sixteen".