216138210 has 64 divisors (see below), whose sum is σ = 535265280. Its totient is φ = 55823040.

The previous prime is 216138203. The next prime is 216138211. The reversal of 216138210 is 12831612.

It is not an unprimeable number, because it can be changed into a prime (216138211) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 168351 + ... + 169629.

It is an arithmetic number, because the mean of its divisors is an integer number (8363520).

Almost surely, 2^216138210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216138210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (267632640).

216138210 is an abundant number, since it is smaller than the sum of its proper divisors (319127070).

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

216138210 is a wasteful number, since it uses less digits than its factorization.

216138210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1463.

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 216138210 is about 14701.6397044683. The cubic root of 216138210 is about 600.1279449371.

Adding to 216138210 its reverse (12831612), we get a palindrome (228969822).

The spelling of 216138210 in words is "two hundred sixteen million, one hundred thirty-eight thousand, two hundred ten".