216918912 has 256 divisors, whose sum is σ = 719124480. Its totient is φ = 56524800.

The previous prime is 216918883. The next prime is 216918917. The reversal of 216918912 is 219819612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216918917) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2147662 + ... + 2147762.

It is an arithmetic number, because the mean of its divisors is an integer number (2809080).

Almost surely, 2^216918912 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 216918912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (359562240).

216918912 is an abundant number, since it is smaller than the sum of its proper divisors (502205568).

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

216918912 is a wasteful number, since it uses less digits than its factorization.

216918912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189 (or 177 counting only the distinct ones).

The product of its digits is 15552, while the sum is 39.

The square root of 216918912 is about 14728.1672994300. The cubic root of 216918912 is about 600.8496407276.

It can be divided in two parts, 21691 and 8912, that added together give a palindrome (30603).

The spelling of 216918912 in words is "two hundred sixteen million, nine hundred eighteen thousand, nine hundred twelve".