11111222121220 has 48 divisors (see below), whose sum is σ = 25130274361920. Its totient is φ = 4102308245376.

The previous prime is 11111222121173. The next prime is 11111222121247. The reversal of 11111222121220 is 2212122211111.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2070451 + ... + 5148709.

It is an arithmetic number, because the mean of its divisors is an integer number (523547382540).

Almost surely, 2^{11111222121220} is an apocalyptic number.

11111222121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11111222121220 is an abundant number, since it is smaller than the sum of its proper divisors (14019052240700).

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

11111222121220 is a wasteful number, since it uses less digits than its factorization.

11111222121220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3092164 (or 3092162 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 11111222121220 its reverse (2212122211111), we get a palindrome (13323344332331).

The spelling of 11111222121220 in words is "eleven trillion, one hundred eleven billion, two hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty".