218312283121 has 3 divisors (see below), whose sum is σ = 218312750361. Its totient is φ = 218311815882.

The previous prime is 218312283067. The next prime is 218312283139. The reversal of 218312283121 is 121382213812.

The square root of 218312283121 is 467239.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a de Polignac number, because none of the positive numbers 2^k-218312283121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218312283181) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 233620 + ... + 700858.

It is an arithmetic number, because the mean of its divisors is an integer number (72770916787).

Almost surely, 2^218312283121 is an apocalyptic number.

218312283121 is the 467239-th square number.

218312283121 is the 233620-th centered octagonal number.

It is an amenable number.

218312283121 is a deficient number, since it is larger than the sum of its proper divisors (467240).

218312283121 is an frugal number, since it uses more digits than its factorization.

218312283121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 934478 (or 467239 counting only the distinct ones).

The product of its digits is 9216, while the sum is 34.

Adding to 218312283121 its reverse (121382213812), we get a palindrome (339694496933).

The spelling of 218312283121 in words is "two hundred eighteen billion, three hundred twelve million, two hundred eighty-three thousand, one hundred twenty-one".