818181818172 has 36 divisors (see below), whose sum is σ = 2068209745056. Its totient is φ = 272723590080.

The previous prime is 818181818171. The next prime is 818181818189. The reversal of 818181818172 is 271818181818.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (818181818171) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4403472 + ... + 4585512.

It is an arithmetic number, because the mean of its divisors is an integer number (57450270696).

Almost surely, 2^818181818172 is an apocalyptic number.

It is an amenable number.

818181818172 is an abundant number, since it is smaller than the sum of its proper divisors (1250027926884).

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

818181818172 is a wasteful number, since it uses less digits than its factorization.

818181818172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306898 (or 306893 counting only the distinct ones).

The product of its digits is 458752, while the sum is 54.

The spelling of 818181818172 in words is "eight hundred eighteen billion, one hundred eighty-one million, eight hundred eighteen thousand, one hundred seventy-two".