21112221101020 has 48 divisors (see below), whose sum is σ = 50687736700608. Its totient is φ = 7235846369280.

The previous prime is 21112221100907. The next prime is 21112221101029. The reversal of 21112221101020 is 2010112221112.

It is a junction number, because it is equal to n+sod(n) for n = 21112221100985 and 21112221101003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112221101029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27003171 + ... + 27774010.

It is an arithmetic number, because the mean of its divisors is an integer number (1055994514596).

Almost surely, 2^{21112221101020} is an apocalyptic number.

21112221101020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112221101020 is an abundant number, since it is smaller than the sum of its proper divisors (29575515599588).

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

21112221101020 is a wasteful number, since it uses less digits than its factorization.

21112221101020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54779950 (or 54779948 counting only the distinct ones).

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

Adding to 21112221101020 its reverse (2010112221112), we get a palindrome (23122333322132).

The spelling of 21112221101020 in words is "twenty-one trillion, one hundred twelve billion, two hundred twenty-one million, one hundred one thousand, twenty".