21111021230020 has 24 divisors (see below), whose sum is σ = 44346773107224. Its totient is φ = 8441812582656.

The previous prime is 21111021229997. The next prime is 21111021230021. The reversal of 21111021230020 is 2003212011112.

It can be written as a sum of positive squares in 4 ways, for example, as 12402962542656 + 8708058687364 = 3521784^2 + 2950942^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21111021229976 and 21111021230003.

It is not an unprimeable number, because it can be changed into a prime (21111021230021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162177649 + ... + 162307768.

It is an arithmetic number, because the mean of its divisors is an integer number (1847782212801).

Almost surely, 2^{21111021230020} is an apocalyptic number.

21111021230020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111021230020 is an abundant number, since it is smaller than the sum of its proper divisors (23235751877204).

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

21111021230020 is a wasteful number, since it uses less digits than its factorization.

21111021230020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324488679 (or 324488677 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21111021230020 its reverse (2003212011112), we get a palindrome (23114233241132).

The spelling of 21111021230020 in words is "twenty-one trillion, one hundred eleven billion, twenty-one million, two hundred thirty thousand, twenty".