21012110112220 has 192 divisors, whose sum is σ = 46789795971072. Its totient is φ = 7913660832000.

The previous prime is 21012110112157. The next prime is 21012110112233. The reversal of 21012110112220 is 2221101121012.

It is a junction number, because it is equal to n+sod(n) for n = 21012110112194 and 21012110112203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10881464655 + ... + 10881466585.

It is an arithmetic number, because the mean of its divisors is an integer number (243696854016).

Almost surely, 2^{21012110112220} is an apocalyptic number.

21012110112220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012110112220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23394897985536).

21012110112220 is an abundant number, since it is smaller than the sum of its proper divisors (25777685858852).

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

21012110112220 is a wasteful number, since it uses less digits than its factorization.

21012110112220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3392 (or 3390 counting only the distinct ones).

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

Adding to 21012110112220 its reverse (2221101121012), we get a palindrome (23233211233232).

The spelling of 21012110112220 in words is "twenty-one trillion, twelve billion, one hundred ten million, one hundred twelve thousand, two hundred twenty".