21111100120220 has 36 divisors (see below), whose sum is σ = 48730002183912. Its totient is φ = 7676763679200.

The previous prime is 21111100120213. The next prime is 21111100120247. The reversal of 21111100120220 is 2202100111112.

It is a junction number, because it is equal to n+sod(n) for n = 21111100120195 and 21111100120204.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4361795126 + ... + 4361799965.

Almost surely, 2^{21111100120220} is an apocalyptic number.

21111100120220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111100120220 is an abundant number, since it is smaller than the sum of its proper divisors (27618902063692).

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

21111100120220 is a wasteful number, since it uses less digits than its factorization.

21111100120220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8723595122 (or 8723595109 counting only the distinct ones).

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

Adding to 21111100120220 its reverse (2202100111112), we get a palindrome (23313200231332).

The spelling of 21111100120220 in words is "twenty-one trillion, one hundred eleven billion, one hundred million, one hundred twenty thousand, two hundred twenty".