181820218404 has 24 divisors (see below), whose sum is σ = 462815101728. Its totient is φ = 55097035840.

The previous prime is 181820218381. The next prime is 181820218453. The reversal of 181820218404 is 404812028181.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 688712817 + ... + 688713080.

It is an arithmetic number, because the mean of its divisors is an integer number (19283962572).

Almost surely, 2^181820218404 is an apocalyptic number.

It is an amenable number.

181820218404 is an abundant number, since it is smaller than the sum of its proper divisors (280994883324).

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

181820218404 is a wasteful number, since it uses less digits than its factorization.

181820218404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377425915 (or 1377425913 counting only the distinct ones).

The product of its (nonzero) digits is 32768, while the sum is 39.

The spelling of 181820218404 in words is "one hundred eighty-one billion, eight hundred twenty million, two hundred eighteen thousand, four hundred four".