218220012 has 72 divisors (see below), whose sum is σ = 584023440. Its totient is φ = 68584320.

The previous prime is 218220001. The next prime is 218220019. The reversal of 218220012 is 210022812.

It is a happy number.

218220012 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (218220019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 42462 + ... + 47322.

Almost surely, 2^218220012 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 218220012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (292011720).

218220012 is an abundant number, since it is smaller than the sum of its proper divisors (365803428).

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

218220012 is a wasteful number, since it uses less digits than its factorization.

218220012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4943 (or 4938 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 218220012 is about 14772.2717278014. The cubic root of 218220012 is about 602.0485643466.

Adding to 218220012 its reverse (210022812), we get a palindrome (428242824).

The spelling of 218220012 in words is "two hundred eighteen million, two hundred twenty thousand, twelve".