21101112201220 has 12 divisors (see below), whose sum is σ = 44312335622604. Its totient is φ = 8440444880480.

The previous prime is 21101112201181. The next prime is 21101112201233. The reversal of 21101112201220 is 2210221110112.

It can be written as a sum of positive squares in 2 ways, for example, as 15437245308676 + 5663866892544 = 3929026^2 + 2379888^2 .

It is a super-4 number, since 4×21101112201220⁴ (a number of 54 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 21101112201194 and 21101112201203.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 527527805011 + ... + 527527805050.

It is an arithmetic number, because the mean of its divisors is an integer number (3692694635217).

Almost surely, 2^{21101112201220} is an apocalyptic number.

21101112201220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21101112201220 is an abundant number, since it is smaller than the sum of its proper divisors (23211223421384).

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

21101112201220 is a wasteful number, since it uses less digits than its factorization.

21101112201220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1055055610070 (or 1055055610068 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21101112201220 its reverse (2210221110112), we get a palindrome (23311333311332).

The spelling of 21101112201220 in words is "twenty-one trillion, one hundred one billion, one hundred twelve million, two hundred one thousand, two hundred twenty".