21112112021020 has 48 divisors (see below), whose sum is σ = 46676386260000. Its totient is φ = 7999092368640.

The previous prime is 21112112021009. The next prime is 21112112021029. The reversal of 21112112021020 is 2012021121112.

It is a junction number, because it is equal to n+sod(n) for n = 21112112020985 and 21112112021003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112112021029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2101395 + ... + 6829354.

It is an arithmetic number, because the mean of its divisors is an integer number (972424713750).

Almost surely, 2^{21112112021020} is an apocalyptic number.

21112112021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21112112021020 is an abundant number, since it is smaller than the sum of its proper divisors (25564274238980).

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

21112112021020 is a wasteful number, since it uses less digits than its factorization.

21112112021020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8936998 (or 8936996 counting only the distinct ones).

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

Adding to 21112112021020 its reverse (2012021121112), we get a palindrome (23124133142132).

The spelling of 21112112021020 in words is "twenty-one trillion, one hundred twelve billion, one hundred twelve million, twenty-one thousand, twenty".