21002120211011 has 4 divisors (see below), whose sum is σ = 21726331252800. Its totient is φ = 20277909169224.

The previous prime is 21002120211001. The next prime is 21002120211013. The reversal of 21002120211011 is 11011202120012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21002120211011 - 2⁶ = 21002120210947 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21002120211013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 362105520851 + ... + 362105520908.

It is an arithmetic number, because the mean of its divisors is an integer number (5431582813200).

Almost surely, 2^{21002120211011} is an apocalyptic number.

21002120211011 is a deficient number, since it is larger than the sum of its proper divisors (724211041789).

21002120211011 is an equidigital number, since it uses as much as digits as its factorization.

21002120211011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 724211041788.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21002120211011 its reverse (11011202120012), we get a palindrome (32013322331023).

The spelling of 21002120211011 in words is "twenty-one trillion, two billion, one hundred twenty million, two hundred eleven thousand, eleven".