21121011122011 has 4 divisors (see below), whose sum is σ = 21126163849000. Its totient is φ = 21115858395024.

The previous prime is 21121011121961. The next prime is 21121011122087. The reversal of 21121011122011 is 11022111012112.

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 21121011122011 - 2³⁷ = 20983572168539 is a prime.

It is a super-2 number, since 2×21121011122011² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121011122311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2576357346 + ... + 2576365543.

It is an arithmetic number, because the mean of its divisors is an integer number (5281540962250).

Almost surely, 2^{21121011122011} is an apocalyptic number.

21121011122011 is a deficient number, since it is larger than the sum of its proper divisors (5152726989).

21121011122011 is an equidigital number, since it uses as much as digits as its factorization.

21121011122011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5152726988.

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

Adding to 21121011122011 its reverse (11022111012112), we get a palindrome (32143122134123).

The spelling of 21121011122011 in words is "twenty-one trillion, one hundred twenty-one billion, eleven million, one hundred twenty-two thousand, eleven".