21021111220000 has 120 divisors (see below), whose sum is σ = 52690845778956. Its totient is φ = 8249794176000.

The previous prime is 21021111219869. The next prime is 21021111220007. The reversal of 21021111220000 is 2211112012.

It can be written as a sum of positive squares in 10 ways, for example, as 671737603216 + 20349373616784 = 819596^2 + 4511028^2 .

It is not an unprimeable number, because it can be changed into a prime (21021111220007) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8855619 + ... + 10975618.

Almost surely, 2^{21021111220000} is an apocalyptic number.

21021111220000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21021111220000 is an abundant number, since it is smaller than the sum of its proper divisors (31669734558956).

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

21021111220000 is an equidigital number, since it uses as much as digits as its factorization.

21021111220000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19831320 (or 19831297 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21021111220000 its reverse (2211112012), we get a palindrome (21023322332012).

The spelling of 21021111220000 in words is "twenty-one trillion, twenty-one billion, one hundred eleven million, two hundred twenty thousand".