216205122 has 64 divisors (see below), whose sum is σ = 505350144. Its totient is φ = 60393600.

The previous prime is 216205117. The next prime is 216205139. The reversal of 216205122 is 221502612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 462733 + ... + 463199.

It is an arithmetic number, because the mean of its divisors is an integer number (7896096).

Almost surely, 2^216205122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216205122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252675072).

216205122 is an abundant number, since it is smaller than the sum of its proper divisors (289145022).

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

216205122 is a wasteful number, since it uses less digits than its factorization.

216205122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703.

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 216205122 is about 14703.9151929002. The cubic root of 216205122 is about 600.1898676885.

Adding to 216205122 its reverse (221502612), we get a palindrome (437707734).

The spelling of 216205122 in words is "two hundred sixteen million, two hundred five thousand, one hundred twenty-two".