21000211021020 has 192 divisors, whose sum is σ = 73312015343616. Its totient is φ = 4363549989120.

The previous prime is 21000211021007. The next prime is 21000211021037. The reversal of 21000211021020 is 2012011200012.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21000211020987 and 21000211021005.

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, 279135129 + ... + 279210351.

It is an arithmetic number, because the mean of its divisors is an integer number (381833413248).

Almost surely, 2^{21000211021020} is an apocalyptic number.

21000211021020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000211021020 is an abundant number, since it is smaller than the sum of its proper divisors (52311804322596).

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

21000211021020 is a wasteful number, since it uses less digits than its factorization.

21000211021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135680 (or 135678 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21000211021020 its reverse (2012011200012), we get a palindrome (23012222221032).

The spelling of 21000211021020 in words is "twenty-one trillion, two hundred eleven million, twenty-one thousand, twenty".