211111011111220 has 48 divisors (see below), whose sum is σ = 492761344658688. Its totient is φ = 75319194354560.

The previous prime is 211111011111191. The next prime is 211111011111311. The reversal of 211111011111220 is 22111110111112.

It is a junction number, because it is equal to n+sod(n) for n = 211111011111194 and 211111011111203.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9052776124 + ... + 9052799443.

It is an arithmetic number, because the mean of its divisors is an integer number (10265861347056).

Almost surely, 2^{211111011111220} is an apocalyptic number.

211111011111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211111011111220 is an abundant number, since it is smaller than the sum of its proper divisors (281650333547468).

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

211111011111220 is a wasteful number, since it uses less digits than its factorization.

211111011111220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18105575640 (or 18105575638 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 16.

Adding to 211111011111220 its reverse (22111110111112), we get a palindrome (233222121222332).

The spelling of 211111011111220 in words is "two hundred eleven trillion, one hundred eleven billion, eleven million, one hundred eleven thousand, two hundred twenty".