181821856364 has 12 divisors (see below), whose sum is σ = 318193800288. Its totient is φ = 90909342000.

The previous prime is 181821856331. The next prime is 181821856373. The reversal of 181821856364 is 463658128181.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 116687 + ... + 614214.

It is an arithmetic number, because the mean of its divisors is an integer number (26516150024).

Almost surely, 2^181821856364 is an apocalyptic number.

It is an amenable number.

181821856364 is a deficient number, since it is larger than the sum of its proper divisors (136371943924).

181821856364 is a wasteful number, since it uses less digits than its factorization.

181821856364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 793096 (or 793094 counting only the distinct ones).

The product of its digits is 2211840, while the sum is 53.

The spelling of 181821856364 in words is "one hundred eighty-one billion, eight hundred twenty-one million, eight hundred fifty-six thousand, three hundred sixty-four".