111211211212220 has 48 divisors (see below), whose sum is σ = 282607313204160. Its totient is φ = 35886642945024.

The previous prime is 111211211212141. The next prime is 111211211212247. The reversal of 111211211212220 is 22212112112111.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 111211211212192 and 111211211212201.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23363697455 + ... + 23363702214.

It is an arithmetic number, because the mean of its divisors is an integer number (5887652358420).

Almost surely, 2^{111211211212220} is an apocalyptic number.

111211211212220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

111211211212220 is an abundant number, since it is smaller than the sum of its proper divisors (171396101991940).

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

111211211212220 is a wasteful number, since it uses less digits than its factorization.

111211211212220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46727399702 (or 46727399700 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 111211211212220 its reverse (22212112112111), we get a palindrome (133423323324331).

The spelling of 111211211212220 in words is "one hundred eleven trillion, two hundred eleven billion, two hundred eleven million, two hundred twelve thousand, two hundred twenty".