12218909138 has 6 divisors (see below), whose sum is σ = 18328598199. Its totient is φ = 6109376406.

The previous prime is 12218909089. The next prime is 12218909173. The reversal of 12218909138 is 83190981221.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 6109454569 + 6109454569 = 78163^2 + 78163^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=78163.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 117245 + ... + 195407.

Almost surely, 2^12218909138 is an apocalyptic number.

12218909138 is a deficient number, since it is larger than the sum of its proper divisors (6109689061).

12218909138 is an frugal number, since it uses more digits than its factorization.

12218909138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156328 (or 78165 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 44.

The spelling of 12218909138 in words is "twelve billion, two hundred eighteen million, nine hundred nine thousand, one hundred thirty-eight".