20211100111220 has 24 divisors (see below), whose sum is σ = 43139102207208. Its totient is φ = 7951908240000.

The previous prime is 20211100111217. The next prime is 20211100111243. The reversal of 20211100111220 is 2211100111202.

It can be written as a sum of positive squares in 4 ways, for example, as 3065769872356 + 17145330238864 = 1750934^2 + 4140692^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20211100111195 and 20211100111204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8283236531 + ... + 8283238970.

It is an arithmetic number, because the mean of its divisors is an integer number (1797462591967).

Almost surely, 2^{20211100111220} is an apocalyptic number.

20211100111220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20211100111220 is an abundant number, since it is smaller than the sum of its proper divisors (22928002095988).

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

20211100111220 is a wasteful number, since it uses less digits than its factorization.

20211100111220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16566475571 (or 16566475569 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 20211100111220 its reverse (2211100111202), we get a palindrome (22422200222422).

The spelling of 20211100111220 in words is "twenty trillion, two hundred eleven billion, one hundred million, one hundred eleven thousand, two hundred twenty".