218818821165 has 16 divisors (see below), whose sum is σ = 400125844608. Its totient is φ = 100031461056.

The previous prime is 218818821163. The next prime is 218818821167. The reversal of 218818821165 is 561128818812.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (218818821163) and next prime (218818821167).

It is not a de Polignac number, because 218818821165 - 2¹ = 218818821163 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218818821163) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1041994282 + ... + 1041994491.

It is an arithmetic number, because the mean of its divisors is an integer number (25007865288).

Almost surely, 2^218818821165 is an apocalyptic number.

It is an amenable number.

218818821165 is a deficient number, since it is larger than the sum of its proper divisors (181307023443).

218818821165 is a wasteful number, since it uses less digits than its factorization.

218818821165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2083988788.

The product of its digits is 491520, while the sum is 51.

The spelling of 218818821165 in words is "two hundred eighteen billion, eight hundred eighteen million, eight hundred twenty-one thousand, one hundred sixty-five".