21021000112021 has 16 divisors (see below), whose sum is σ = 25873371216000. Its totient is φ = 16631118681408.

The previous prime is 21021000112009. The next prime is 21021000112037. The reversal of 21021000112021 is 12021100012012.

It is not a de Polignac number, because 21021000112021 - 2⁹ = 21021000111509 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a junction number, because it is equal to n+sod(n) for n = 21021000111992 and 21021000112010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021000115021) 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, 4391626 + ... + 7831243.

It is an arithmetic number, because the mean of its divisors is an integer number (1617085701000).

Almost surely, 2^{21021000112021} is an apocalyptic number.

It is an amenable number.

21021000112021 is a deficient number, since it is larger than the sum of its proper divisors (4852371103979).

21021000112021 is a wasteful number, since it uses less digits than its factorization.

21021000112021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12241788.

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

Adding to 21021000112021 its reverse (12021100012012), we get a palindrome (33042100124033).

The spelling of 21021000112021 in words is "twenty-one trillion, twenty-one billion, one hundred twelve thousand, twenty-one".