21111111201011 has 64 divisors (see below), whose sum is σ = 24017720832000. Its totient is φ = 18420596812800.

The previous prime is 21111111201007. The next prime is 21111111201031. The reversal of 21111111201011 is 11010211111112.

It is not a de Polignac number, because 21111111201011 - 2² = 21111111201007 is a prime.

It is a super-2 number, since 2×21111111201011² (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 (21111111201031) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3945261986 + ... + 3945267336.

It is an arithmetic number, because the mean of its divisors is an integer number (375276888000).

Almost surely, 2^{21111111201011} is an apocalyptic number.

21111111201011 is a deficient number, since it is larger than the sum of its proper divisors (2906609630989).

21111111201011 is a wasteful number, since it uses less digits than its factorization.

21111111201011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6564.

The product of its (nonzero) digits is 4, while the sum is 14.

Adding to 21111111201011 its reverse (11010211111112), we get a palindrome (32121322312123).

The spelling of 21111111201011 in words is "twenty-one trillion, one hundred eleven billion, one hundred eleven million, two hundred one thousand, eleven".