21011002110021 has 96 divisors (see below), whose sum is σ = 36421312435200. Its totient is φ = 10648237259520.

The previous prime is 21011002109989. The next prime is 21011002110067. The reversal of 21011002110021 is 12001120011012.

It is not a de Polignac number, because 21011002110021 - 2⁵ = 21011002109989 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21011002109979 and 21011002110006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011002112021) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 58156425 + ... + 58516593.

It is an arithmetic number, because the mean of its divisors is an integer number (379388671200).

Almost surely, 2^{21011002110021} is an apocalyptic number.

21011002110021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21011002110021 is a deficient number, since it is larger than the sum of its proper divisors (15410310325179).

21011002110021 is a wasteful number, since it uses less digits than its factorization.

21011002110021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361079 (or 361072 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21011002110021 its reverse (12001120011012), we get a palindrome (33012122121033).

The spelling of 21011002110021 in words is "twenty-one trillion, eleven billion, two million, one hundred ten thousand, twenty-one".